Geo route OTAL PN11 FROM BROTO TO BUJARUELO AND OTAL VALLEY c Sobrarbe Geopark

Texts: The Geo-Routes PN are taken from the Geological Guide Ordesa and Monte Perdido National Park" from the Collection of Geological guides of the National Parks (IGME-OAPN, Roberto Rodríguez Fernández, dir and coord.) The texts of these Geo-routes have been developed by Alejandro Robador Moreno, Luis Carcavilla Urquí, Josep Maria Samsó Escolá and Ánchel Belmonte Ribas (Scientific Coordinator Sobrarbe Geopark). Figures and illustrations, by Albert Martinez Ríus, and photographs by Josep María Samsó Escolá, Luis Carcavilla Urquí, Alejandro Robador Moreno and Ángel Salazar Rincón

Translation into French and English: Trades Services, S.L.

Design and layout: Pirinei, S.C.

CBC project Pyrenees-Monte Perdido, World Heritage (PMPPM) GEO- of the 2007-2013 POCTEFA Program. ROUTE NETWORK OBRARBE GEOPARK GEO-ROUTE S NETWORK The Sobrarbe Geopark is located in the north of the province of Huesca and coincides with the district of the same name. This area is noted for its many cultural and natural values, most notably its spectacular . Indeed, the Geo-Route network of the Sobrarbe Geopark was created to learn about and understand its geological heritage in greater depth. This is a network of 30 self-guided routes that allow visitors to access the most outstanding geological sites in the district and understand their origin, meaning and significance. All Geo-Route have been designed so that they can be covered on foot and are clearly signposted; in most cases they are based on official short-route (PR) or long-route (GR)except PN 1, PN 4, PN 5, PN 9, PN 10 and PN 11 that combine a stretch of road and vehicle with trails paths. There is a brochure on each route in order to facilitate the interpretation of each stop on the way. In addition, 11 of these geological routes are located in the Ordesa and Monte Perdido National Park, including the territory of the Geopark, and 3 of the Geo-routes are of a cross-border nature, allowing visitors to enjoy the geological heritage of the Pyrenees-Monte Perdido, declared a World Heritage Site by UNESCO.

In addition to the Geo-Route network, there are mountain bike (MTB) routes in the Geopark, some of which feature small information panels along the way and there is also a brochure that Taken together, these routes will enable visitors to enjoy the most beautiful parts of the Sobrarbe district and also obtain further information on its long geological history dating back over 500 million years. THE SOBRARBE GEOPARK In 2006 the Sobrarbe District was declared a Geopark and became part of the European Geopark Network, sponsored by UNESCO. A Geopark is a district with unique geological features for which a sustainable development strategy has been developed. Consequently, the key objective is to preserve its natural and cultural heritage and promote development through the appropriate management of the geological environment. There are currently 60 Geoparks in Europe and 100 in the word. The Sobrarbe Geopark features an exceptional geological environment, with over 100 places of geological interest that have been inventoried; many of which can be visited on the Geo-Route network. More info: www. geoparquepirineos.com

1 AP OF THE SOBRARBE GEOPARK M GEO-ROUTE NETWORK

Gèdre Aragnouet

Gavarnie

Bujaruelo Pineta Monte Viadós Perdido Río Cinca A-138 Bielsa PARQUE Víu Torla P.N. DE ORDESA Y NATURAL MONTE PERDIDO DE Broto POSETS- Escuaín MALADETA Fanlo Gistaín San Juan de Plan Ara Saravillo Nerín Plan Río Puértolas Lafortunada Fiscal Laspuña

N-260 Ascaso

Escalona

Labuerda San San Juan de Toledo Boltaña Victorián Foradada Aínsa N-260 Campo

Las Bellostas Embalse de Tierrantona Mediano PARQUE NATURAL Arcusa DE LA SIERRA Y Palo LOS CAÑONES DE Paúles Samitier GUARA de Sarsa

Río Esera

Bárcabo Abizanda Lecina Embalse de

A-138 El Grado

GEO 1 Geo-Route PN 1 Geo-Route in National Park of Ordesa and Monte Perdido

The various Sobrarbe geo-routes vary in length, difficulty, theme and duration. Consequently, almost everyone will be able to find a route that suites them.

2 Nº GEO-ROUTE TRAVEL DIFFICULTY DURATION THEME*

1 Geopark Interpretation Centre Geopark area - 1 hour All Aínsa: a town between two . 2 Urban geology Aínsa Low Short R T F Samitier castle and 3 Low Medium TF Geology: A bird's eye view hermitages 4 Inside the Congosto de Entremón Medium Short TR Vero canyon 5 Breath-taking landscapes of water Low Medium RF and viewpoints 6 Sobrarbe at your feet Ascaso- Nabaín Medium Medium TF

7 Crossing the Jánovas Gully Near Jánovas Medium Short TR

8 Iron Age Elements Viu-Fragén-Broto Low Short GR Medium- 9 Long Whims of water for lonely mountaineers Ordiso Valley High GKR A lake among the oldest rocks in 10 Sobrarbe Lake Pinara and Puerto Viejo Low Medium GR

11 The hidden lake Lake Bernatuara Medium Long RGT

12 A road with tradition Bujaruelo Pass Medium Medium RGT Fiscal-Gradatiello- High 13 A privileged vantagepoint Peña Canciás Long RT

14 Secrets of the Guara Mountains Las Bellostas-Sta. Marina Low Long FRT Low 15 Geology for the Saint Espelunga de San Victorián Short RT

16 A passage between two worlds Collado del Santo Medium Long RFT Low 17 Water inside the Earth Badaín-Chorro de Fornos Medium KR Basa de la Mora Low 18 The Jewel of Cotiella (Ibón de Plan) Short GR

19 Treasures of the Posets-Maladeta Viadós-Ibones de Millars Medium Long GR Nature Park GEO-ROUTE IN NATIONAL PARK OF ORDESA AND Nº MONTE PERDIDO TRAVEL DIFFICULTY DURATION THEME*

Torla-Cola de Caballo- Low- RGF PN1 Ordesa Valley Góriz Shelter Medium** Medium Góriz Shelter-Mount Perdido PN2 Mount Perdido High Long TRKGF

PN3 The Roland Gap Góriz Shelter - Roland Gap High Long TRKGF

PN4 Cutas Viewpoints Torla-Viewpoints-Nerín Low** Medium KRGFT Low** PN5 La Larri Bielsa-La Larri Valley Medium RGT High PN6 Balcon de Pineta Pineta-Balcón de Pineta Long FTG Medium PN7 Añisclo Canyon (lower part) San Urbez-Fuen Blanca Long RGT

PN8 Añisclo Canyon (upper part) Fuen Blanca-Añisclo Pass High Long RGTF Escalona-Puyarruego PN9 Circuit Añisclo Canyon Low** Medium RTK Tella, Revilla-Escuaín PN10 Escuaín Valley Low** Medium TK Broto -Bujaruelo- PN11 Otal Valley Otal Valley Low** Medium GTK * Theme: T- Tectonics; F- Fossils;K- Karst; R- Rocks; E- Stratigraphy; G- Glaciarism ** Combining vehicle and hiking

3 GEOLOGICAL HISTORY OF THE SOBRARBE GEOPARK The geological history of the Sobrarbe Geopark goes back over 500 million years. Many geological events that have affected the landscape and relief took place over that vast period of time. The geological history of Sobrarbe can be divided into 6 different episodes, each of which includes significant moments that led to today's geological landscape.

THE REMOTEST PAST 1 (between 500 and 250 million years ago) Over a long period of the Palaeozoic, the land now occupied by Sobrarbe was a seabed where silt, mud, clay and sand accumulated. Today these have become the shale, sandstone, limestone and quartzite that form the northern mountains and valleys of the District. These rocks were intensely altered by the Variscan orogeny: an episode of intense tectonic activity that affected much of Europe and resulted in a huge mountain range. Numerous folds and faults attest to this past together with granite that was also formed in that era.

Folds in Palaeozoic rocks

TROPICAL MARINE SEDIMENTATION 2 (between 250 and 50 million years ago) The giant mountain range formed in the previous stage was heavily eroded and almost disappeared. Once has almost swept away the mountain range, the resulting flat land was covered by a shallow tropical sea. Coral reefs appeared and the calcareous mud we see today in the shape of limestone, dolomite and marl, containing abundant marine fossils, accumulated. The sea fluctuated several times and there were many time when its depth increased and decreased; however, it practically covered the area throughout this episode. Fossils of marine organisms in the Cretaceous limestone

THE FORMATION OF THE PYRENEES 3 (between 50 and 40 million years ago) The marine sedimentation process continued during this episode, but under very different conditions to previous episodes. The sea, which separated what is today the Iberian Peninsula from the rest of Europe, gradually dried up. About 45 million years ago, as this sea became narrower and sedimentation occurred on the seabed, thousands of Typical landscape of turbidites outcrops metres below the surface, on land, the Pyrenees began to develop. I

In Sobrarbe we can find exceptional examples of turbidites, rocks formed in that sea as it accumulated huge amounts of sediments resulting from the development of the mountain range, while the mountains continued to develop.

PALAEOZOIC 542 m.a. 488 m.a. 443 m.a. 416 m.a. 359 m.a. 299 m.a. 251 m.a. 199 m.a. 145 m.a. 65 m.a. 23 m.a. 2,5 m.a.

Cambrian Ordovician Silurian Devonian Carboniferous Permian Tria Jurassic Cretaceous Palaeogene Neogene Quaternary EPISODES: 1 4 SOBRARBE GEOPARK THE SOBRARBE DELTAS (between 40 and 25 million years ago) 4 The formation of the mountain range caused the gradual disappearance of the sea, which was becoming shallower and elongated. About 40 million years ago, a system of deltas marked the transition between the area that had emerged and later stages of this marine gulf. Although this period was relatively short, huge amounts of accumulated, which can be found today in the southern part of the District converted into marl, limestone and sandstone. Once the sea had retreated definitely from Sobrarbe, the relentless effects of erosion became all the more intense if possible. About 25 million years ago, active and dynamic torrents accumulated huge amounts of that, over time, became conglomerates, such as those that form the bulk of Conglomerates: rocks formed from rounded Peña Canciás. fragments of other rocks

THE ICE AGES 5 (last 2,5 million years) Once the mountain range and its foothills had formed, erosion began to transform it. The river valleys widened and the present river network began to be formed. On several occasions during the Quaternary, mainly over the last two and a half million years, various cold spells occurred, covering the mountains with snow and ice. The last major ice age reached its peak about 65,000 years ago. Huge covered the valleys and mountains and shaped the landscape, effectively eroding some places and accumulating sediment in others. The landscape of the entire northern section of the District was shaped by those ancient glaciers.

Glaciers like the ones we see today in the covered the Pyrenees at that time 6 TODAY Today, erosion processes are slowly and gradually wearing away the mountain range. This erosion occurs in many ways: through the action of rivers, erosion on the slopes, karst dissolution, etc. The landscape that we see today is only an instant in a long evolutionary process that is on-going, but now with the participation of man who is changing the environment like no other living being is capable.

Río Cinca, agente modelador actual

MESOZOIC CENOZOIC 199 m.a. 145 m.a. 65 m.a. 23 m.a. 2,5 m.a.

Tria Jurassic Cretaceous Palaeogene Neogene Quaternary 2 3 4 5 6 5 PISODES REPRESENTED IN THE GEO- E ROUTES

Nº GEO-ROUTE EPISODES

PN1 Ordesa Valley 2 5 6

PN2 Mount Perdido 2 3 5 6

PN3 The Roland Gap 2 3 5 6

PN4 Cutas Viewpoints 2 3 5 6

PN5 La Larri 1 3 5

PN6 Balcon de Pineta 2 3 5 6

PN7 Añisclo Canyon (lower part) 2 5 6

PN8 Añisclo Canyon (upper part) 2 3 5

PN9 Circuit Añisclo Canyon 3 6

PN10 Escuaín Valley 3 6

PN11 Otal Valley 1 3 5 6

Episode 1: Variscan orogeny - Episode 2: Tropical marine sedimentation - Episode 3: The formation of the Pyrenees - Episode 4: The Sobrarbe deltas- Episode 5: The ice age - Episode 6: Today Nº GEO-ROUTE EPISODES

1 Geopark Interpretation Centre 1 2 3 4 5 6 Aínsa: a town between two rivers. 2 Urban geology 3 6 3 Geology: A bird's eye view 2 3 6

4 Inside the canyon 2 3 6 Breath-taking landscapes of water 5 and rock 2 4 6 Sobrarbe at your feet 6 3 6

7 Crossing the Jánovas Gully 3 6

8 Iron Age Elements 5 6

9 Whims of water for lonely mountaineers 5 6

10 A lake among the oldest rocks in Sobrarbe 1 5

11 The hidden lake 1 2 5 6

12 A road with tradition 1 2 5

13 A privileged vantagepoint 4 6

14 Secrets of the Guara Mountains 2 6

15 Geology for the Saint 2 3 A passage between two worlds 16 2 3 Water inside the Earth 17 2 6 The Jewel of Cotiella 18 2 5 6 Treasures of the Posets-Maladeta 19 Nature Park 1 5 6

7 8 Geo OTAL route11 PN11 VALLEY

FROM BROTO TO BUJARUELO AND OTAL VALLEY

Route along the River Ara glacial features of that valley. After which enables us to cross the Mount visiting Torla, a visit to the former Perdido unit and made interesting Ordesa state hotel - currently the visitor observations regarding its glacial past. centre - will enable us to view the tectonic structure of the Mount The route starts in Broto, where Perdido mantle before heading to we can view the spectacular Sorrosal Bujaruelo. The final section leads up . The tour makes its way up the the surprisingly well-preserved Otal River Ara valley but it is advisable to glacial valley. turn-off to Linás de Broto to view the

9 7 8 i LEGÉNDE N 9 250 m 6 i Home Geo-Route Tour Geo-Route Walking Tour 1 Number of stop 5

4

2 3

1 i

LA GEO-ROUTE PN11 PN 11 Broto Valley allows us to visit some areas that are essential if we want to understand the geological history of the Ordesa and Monte Perdido National Park.

We advise taking this route any time other than July and August, when access to the Park is only allowed by bus.

Except at Easter and on the Virgin of the Pilar bank holiday, access by private vehicles is allowed the rest of the year, which will enable us to visit the former Hotel, Cars can reach as far as San Nicolás de Bujaruelo along a road through the woods and, from there, we advise proceeding on foot, along a magnificent forest path, closed to traffic, to the Otal refuge. Stop 3: The Roca de la Pillera (Pillera Rock), an impressive rock that corresponds to a platform fragment that became detached and fell into the turbidite basin.

Stop 1: Broto, with the Stop 5: View of the Park's most spectacular Sorrosal waterfall in the geological structure from the Hotel. background.

Stop 8: Otal Valley, a beautiful example of a U- shaped valley caused by the action of a . Stop 9: Panoramic view and a magnificent lesson in structural geology of the area.

Fig. 1. Route Scheme 11 BROTO AND THE SORROSAL WATERFALL stop 1 Broto avec la cascade de Sorrosal au fond.

WHAT WE CAN SEE - A spectacular waterfall. Stratified rocks - A typical glacial valley. Example of turbidite layers

This route has been described from Broto to Otal and combines a possible tourist visit by car with an easy and pleasant walk, accessible to any visitor. It is advisable to take this tour outside the summer months, when private cars are allowed into the National Park. This will enable us to reach the former hotel and the Pradera road. We shall start the visit in Broto, contemplating the Sorrosal waterfall, where there are information panels of the Roadside Geological Route of Sobrarbe Geopark. All the waterfall is equipped as a via ferrata and geologically interpreted through a brochure published by the Sobrarbe Geopark. like this one are typical of ancient glacial valleys, as the glaciers converge at different altitudes and, when the ice retreats, the side valleys are left hanging above the main valleys. This is precisely the case of the Sorrosal waterfall, which drops down the difference in altitude between the hanging valley of Fragén and Linás de Broto and the course of the River Ara. The exposure of the rock to the waterfall displays the typical appearance of Hecho group (T7) turbidite layers. We can see thin resistant ochre-coloured layers Fig. 2. The charming town of Broto with the Sorrosal waterfall in the consisting of sandstone that are interspersed background. The strata we can see are alternating layers of sandstones and lutite and they correspond to Eocene turbidites. with softer grey layers that correspond to clay and marl sections. To the left of the waterfall, there is a tight anticlinal fold. FRAGEN AND LINÁS DE BROTO stop2

WHAT WE CAN SEE - A valley with a flat floor. - Well-preserved glacial landscapes

Before proceeding towards Torla, we Back at the Torla junction, we will be shall make our way up the road to the able to see the town of Fragén, with remains of Cotefablo pass and to Linás de Broto. The glacial moraines and the Sorrosal ravine lateral moraine of Vio de Broto, that blocked embedded in the southern section of the valley. the valley during the last Ice Age, can be This is a splendid route if you want a detailed seen from the town. view a glacial landscape.

The sedimentary fill of this blocked and A more complete description of the hanging valley, together with some lacustrine glaciers characteristics of this valley can be sediments, can be seen beneath the road, in the found on the Geo-Route 8. shape of thick horizontal sediments.

Fig. 3. The town of Linás de Broto is in a side valley, corresponding to a former hanging glacial valley. The grey sediments we can see under the road are deposits of an ancient lake. They settled there when the main moraine in the Ara Valley blocked the valley, forming a natural dam.

13 TORLA AND PILLERA ROCK stop 3

WHAT WE CAN SEE - A large limestone rock - Sediments in deep sea areas

Fig. 4. Pillera Rock seen from street in which the Torla Church stands. It is a huge block of limestone from the platform that moved into the Eocene turbidite basin. Our next stop will be Torla, which we correspond to traces caused by water and fossils can take some time to visit. A key element at all of worms and other organisms that used to live times is the view of the entrance to Ordesa, with on the sediment. the Cebollar fold and views of the Mondarruego walls, described in other routes. We propose a We also recommend a visit to the walk to the church, from where there are National Park interpretation centre located next splendid views. Direct your attention to the to the large car park and that also housed the Pillera Rock, a large limestone block that is information office. completely different to any other rocks in the vicinity.

The explanation is that this is a resedimented rock within turbidities. We must remember that turbidites are rocks that settled in a deep sea. These turbidites are visible before reaching the town and also in rocky outcrops that can be seen among the houses. We may also notice that the slabs used to pave the Fig. 5. Diagram explaining that the Pillera Rock is a huge fragment of the streets are made from turbidites from the area, in continental shelf that has moved within the turbidite basin. which we can find marks and grooves that

14 SAN ANTÓN CAMP SITE stop 4

WHAT WE CAN SEE - A narrow pass flanked by two rocks - We are on the Mount Perdido thrust fault.

There is a small car park at the right as we look towards Mondarruego), we junction leading to the San Antón camp site, can see Mount Duáscaro, where there are with views of the entrance to the valley along some folds forming a very complicated the Turieto path. structure.

At this point, we are actually on the This peak is a twin of Tozal del Mount Perdido thrust fault and there are Cebollar, which is directly above us and, intensely folded Gallinera Limestone rocks on therefore, we will be unable to see its either side of the valley. To the east (to our beautiful folds from our position.

Fig. 6. Magnificent outcrop, visible from the San Antón camp site, of the Mount Perdido thrust fault. We can see how the Estrecho Limestone overlap the Hecho Group (Eocene) turbidites; about 70 million years younger.

15 HOTEL AND PRADERA ROAD stop 5 The hotel affords one of the most spectacular geological views of National Park

WHAT WE CAN SEE - A view of many types of rock - The Mount Perdido thrust fault displaying repetitions of its stratigraphy.

Entrance to the park in private vehicles is permitted except in the high season. It is the perfect occasion to reach the former Ordesa Hotel in comfort and access the Pradera Road, where we can enjoy interesting views. The hotel affords one of the most famous geological views of the Mount Perdido thrust fault, as described by Seguret in 1967. It is certainly the most frequently visited and well- known geological point of the Park.

The point on the road, known as Tramasaguas, near the Turieto waterfall, provides a view of the devastating effects of an avalanche. Fig. 7.Spectacular view of Mount Perdido from the hotel. We can clearly Originating on the Mondaruego cliffs and see the Marboré sandstone (K3, Late Cretaceous) arranged in the middle descending along the Tramasaguas channel, it of the overthrust surface above Palaeocene T1-T3 and Eocene T7 rocks. literally crushed a section of the forest, where we can see a fan-shaped area of fallen tree trunks. The valley is full of avalanche channels, with small alluvial fans.

Fig. 8.There are frequent avalanches in the area in winter that destroy the forest. When the snow has melted, they can easily be identified by a change in colour of the vegetation. Light green corresponds to new vegetation that has grown in the devastated area. This photograph shows fallen and destroyed trees forming a fan shape after an avalanche. NEW BRIDGE AT SANTA ELENA AND THE CAMP SITE stop 6

WHAT WE CAN SEE - A deeply embedded valley - This is a river valley

On the way to Santa Elena, we the action of the river. It is clear that the shall pass Puente de los Navarros and take origins are glacial but that karstic action the Bujaruelo forest track. Here, we shall be and the tremendous force of river floods able to see a cut in the Salarons dolomites have definitely "redesigned" the profile, and Gallinera limestone at the side of the transforming it into a river valley. track. From the new bridge at Santa Elena, we shall take alternative routes along The Fuen is located near the ca mp site. mountain paths belonging to the GR-11, This is a karst spring that drains the towards the South or North. Arañonera system, one of the most spectacular underground cave systems in The valley is extremely deep due to the Pyrenees.

Fig. 9. View o the River Ara valley, from the road to the Bujaruelo Pass, with the location of the Santa Elena spring. It is the spring of the Arañonera system, a network of underground caves and sinkholes measuring over 44 kilometres long and covering a vertical distance of 1,349 metres, the third longest in the Pyrenees. The T1 is at the top; one of the many cavities that lead to the interior.

17 THE ARAÑONERA UNDERGROUND CAVE SYSTEM

!!An extensive underground cave system exists in the Tendeñera Mountain Range, to the west of the River Ara and beneath Arañonera or Otal peak. It covers a difference in altitude of 1,349 metres and is over 43 kilometres long. It is the 21st largest cave in the world and the 6th in Spain regarding vertical length. It has several entrance points and an underground route can be taken from the highest point (Foratón) to the spring (Santa Elena), covering a distance of almost 10 kilometres and a vertical drop of 1,388 metres. This is the route with the longest vertical distance between the top and lower points in the world.

Karstification has developed in the tertiary limestone layers that are not very thick but are in a vertical position due to tectonic forces. The lower part is formed of Marboré sandstone, which acts as a waterproof level. This is why the underground system is aligned in an east-west direction and the upper entrance is located at such a great altitude (2,687 metres). In general, the system consists of a series of galleries running east-west, at different depths and crossed by wells. The deeper levels feature underground rivers that carry the water to the main spring, Santa Elena cave, located 150 metres above the River Ara.

Its karstic origins are very ancient, from the late Miocene, early Pliocene (over 5 million years). It has several phases and, at the beginning, was binary in nature. In other words, the surface rivers penetrated underground and became underground rivers. This is the reason for the large upper galleries, which would be impossible to generate now given the limited absorption power of the basin. The evolution of this system must be related to the successive ice ages that defined the various base levels. There are series of caves with moraine sediments linked to the blockage of cavities by ice. THE GREATES SINKHOLES IN THE WORLD

NAME COUNTRY LENGTH DIFFERENCE IN ALTITUDE 1 Krubera (Voronja) Georgia 16,058 2,197 2 Sarma Georgia 6,370 1,830 3 Illyuzia-Mezhonnogo-Snezhnaya Georgia 24,080 1,753 4 Lamprechtsofen Vogelschacht Austria 38,000 1,632 5 Gouffre Mirolda / Lucien Bouclier France 13,000 1,626 6 Réseau Jean Bernard France 20,536 1,602 7 Torca del Cerro del Cuevon Spain 7,060 1,589 8 Sistema Huautla Mexico 64,283 1,545 9 Shakta Vjacheslav Pantjukhina Georgia 5,530 1,508 10 Sima de la Cornisa - Torca Magali Spain 6,445 1,507 11 Cehi 2 Slovenia 5,291 1,502 12 Sistema Cheve (Cuicateco) Mexico 26,194 1,484 13 Sistema del Trave Spain 9,167 1,441 14 Evren Gunay Dudeni Turkey 3,118 1,429 15 Sustav Lukina jama Croatia 1,078 1,421 16 Boj-Bulok Uzbekistan 14,270 1,415 17 Gouffre de la Pierre Saint Martin France/Spain 80,200 1,408 18 Sima de las Puertas de Illaminako Spain 14,500 1,408 19 Kuzgun Cave Turkey 3,187 1,400 20 Abisso Paolo Roversi Italy 4,000 1,350 21 Sistema Aranonera Spain 44,682 1,349

Speleological activities began in 1972, when the speleologists from the Equip de Recerques Espelològiques of the Centre Excursionista de Catalunya discovered and began to explore pothole T1. In 1976, the link of this cavity to the Santa Elena spring was finally made, with a vertical distance of -620 metres. New cavities were gradually discovered to the west and at higher altitudes and eventually incorporated to the underground system. The connection of sinkhole S1 with the T1 in 1987 must be highlighted as it gave rise to a 26 km system with a vertical distance of 1,179 m, the longest route in the world at the time. After numerous explorations and the discovery of new sinkholes, the Foratón de Tendeñera was finally connected to the rest of the galleries in 2003. This sinkhole is located at an altitude of 2,687 metres. Therefore, the difference in altitude is now 1,349 m (-1,338 m + 11 m) and the total length exceeds 43 kilometres. Over the years, several speleological groups have particpated, such as: Equip de Recerques Espelològiques (ERE del CEC), Grup d’Investigacions Espeleològiques del Club Excursionista de Gràcia (GIE), Espeleo Club de Gràcia (ECG), Grup Geogràfic de Gràcia (GGG), Agrupació Espeleològica Ramaliega (AER) and the Sección de Espeleologia de la Sociedad Excursionista de Málaga, among others. SAN NICOLÁS DE BUJARUELO stop 7

WHAT WE CAN SEE - A very deep valley - The route leads through Estrecho Limestone

As we approach San Nicolás de Otal Forest track, closed to traffic. It is also Bujaruelo, we shall be able to see the Estrecho possible to take the alpine track that leads to Limestone layers clearly, affected by Bujaruelo Pass and, further on, to Gavarnie or the detachments and minor thrust faults. Serradets refuge, below the Brèche de Roland.

The route by car ends at San Nicolás The view of the valley and of Mount and, if we want to continue we must take the Otal from the track is magnificent.

Fig. 10. View of San Nicolás de Bujaruelo. This is the end of the road and a track or path continues to the Bujaruelo Pass.

21 ENTRANCE TO OTAL VALLEY stop 8 Otal Valley with classic U-shaped profile caused by glacial erosion.

WHAT WE CAN SEE - A U-shaped valley - This is a typical glacial valley

At the beginning of the walk to Otal, we shall be able to see the main River Ara valley. We shall climb to the hanging valley of Otal following the bends in the track, completely resting on a great lateral moraine that closes the valley. Near the pass, we shall clearly see the western side of Mount Mondaruego, where we shall be able to distinguish a system of overlapping thrusts faults that repeat sections of Gallinera Limestone. Associated with these, there are also anticlinal folds.

We must remember that we can see these anticlines from the front along the southern slopes of the mountains in the park, as if they were rollers, while the thrust planes are difficult to see. However, this side allows us to understand their structural layout much better. The arrival at the pass and the entrance of Otal Valley is splendid. We are on the remains of a moraine, Fig. 11. Otal Valley with classic U-shaped profile caused by glacial erosion. which includes large blocks of Marboré The Mount Perdido massif in the background. Sandstone.

Fig. 12. Erratic block. This is a large rock that has been moved by the ice and placed among rocks of a different type.

22 WOMEN EXPLORERS: !! THE ASCENT TO THE BRÈCHE DE ROLAND BY THE DUCHESS OF BERRY IN 1828.

There is an inscription on the eastern slope of the Brèche de Roland with the names of some aristocrats and a date. Erosion has made the text difficult to read but it originally said:

" MARIE CAROLINE DE NAPLES, DUCHESSE DE BERRY, DUCHESSE DE REGGIO, MARQUISE DE PODENAS, COMTE DE MESNARD, COMTE DE MAILLY, MARQUIS DE VERDALLE, COMTE DE SERRANT, CHEVALIER DE LA ROUZIÈRE - 29 AOÛT 1828 ".

The inscription was made to commemorate the ascent to the Brèche de Roland by Marie Caroline of Naples and her companions on August 29, 1828. This young noblewoman is noted among female hikers as the first woman to reach this mythical mountain pass. Marie Caroline of Naples (1798-1870), Duchess of Bourbon -Two Sicilies , daughter of Francis I of Naples, King of the Two Sicilies. In June, 1816, she married Charles, Duke of Berry, son of the Count of Artois, who would become the future Charles X of France. Her husband was murdered in 1820 and his posthumous son, Henri, became the pretender to the throne of France. In 1828, the Dowager Duchess was travelling through France on a propaganda tour supporting the royal cause on behalf of her son.

This is how she arrived at the spa centres in the Pyrenees, fashionable places of high society at the time. Due to her royal rank, she was accompanied by a large retinue. She arrived in Saint-Sauveur on July 28, where, apart from enjoying the thermal cures, she spent time drawing. Thus, she became enthused with the grandiose landscapes in the area. Eventually, she started to go on walks in the area which gradually became more difficult, although she was often carried in a sedan chair.

On the expedition to the Brèche de Roland, the Duchess and her companions were attended by thirty guides. The route from Saint-Sauveur to Gèdre was made on horseback. Once there, they visited the cave and spent the night in the Gavarnie . The following day, they set out at 4:30, this time in a sedan chair. The first stop was to admire the cirque and waterfall. They then made their way up the "Écheles" section on foot and the put on crampons to cross the snow fields and the glacier, where workers had prepared some steps the previous day. At 11 o'clock, they reached the Brèche, where they had lunch on the Aragon side.

Perhaps the Duchess of Berry was not a great sports woman but she had the merit of breaking down social barriers that affected women at the time. This excursion was certainly a bold way of going down in history. OTAL HUT stop 9

WHAT WE CAN SEE - A spectacular view revealing the different strata - Numerous stratigraphic units, folds and trust faults

It is advisable to follow the forest track to the Otal Hut, a shelter used by shepherds, from where we can pass to the alpine tracks.

The valley's U-shape is clearly visible; another example of flat valleys. From this point, we can also see the Bujaruelo Mountain Pass and the Palaeozoic rocks of the Bernatuara limestone ridges. These are the Palaeozoic materials of the Gavarnie mantle, which, from this valley to the west, no longer reveals its basal thrust fault To futher explore in this description you can consult the Geo Routes 11 and 12.

Fig. 13. Geological view from Otal Valley. There is a Palaeozoic base in the lower area on the left (north) and a small series of Late Cretaceous (K1). Further up, the Gavarnie mantle with Late Cretaceous materials (K1 and K2). These materials are overlapped by the Mount Perdido mantle, with a powerful series of Marboré sandstone (K3) and Palaeocene sandstone (T1). We can see several small thrust faults that repeat and fold Marboré (K3), Palaeocene (T1) and Eocene (T6) materials at the top of the view.

Fig. 14. General diagram with the approximate location of what can be seen in the panoramic photograph.

24 PYRENEES-MONTE PERDIDO, !!A TERRITORY BORDER WORLD HERITAGE In 1997, UNESCO added the Pyrenees-Monte Perdido site to its World Heritage List in recognition of its natural and cultural importance. The site covers a cross-border area and includes the Gèdre, Gavarnie and Aragnouet valleys in France and the district of Sobrarbe in Spain.

This remarkable mountainous landscape straddles the border between France and Spain. At its centre lies the limestone Monte Perdido from Mountain Sesa Photo Archive Sobrarbe County. Nacho Pardinilla massif of Monte Perdido. The Pyrenees- Monte Perdido World Heritage Site extends across 31,189 hectares and includes the municipalities of Torla, Fanlo, Tella-Sin, Puértolas, Bielsa and Broto in Sobrarbe on the Spanish side and the Gèdre, Gavarnie and Aragnouet valleys in the Hautes-Pyrénées Department on the French side. The entire Ordesa and Monte Perdido National Park in Spain lies within the listed site, while in France the area is also protected by the Pyrenees National Park. Gavarnie Cirque. Photo Archive Sobrarbe County. Nacho Pardinilla Cultural and natural heritage

The Pyrenees-Monte Perdido is home to deep and cirques with spectacular walls: three canyons and a gorge on the southern side in Spain (Ordesa, Añisclo, Pineta and Escuaín) and four large glacial cirques on the northern side in France, which is steeper (Gavarnie, Estaubé, Troumouse and Baroude). The karstic, glacial and valley landscapes contrast with the almost flat-topped peaks and the underground waters that have formed extensive galleries, chasms and grottoes.

This single site thus harbours outstanding cultural and natural aspects: The geological and biological characteristics of the site make it an extremely interesting place for science and conservation, as it includes numerous endemic species of flora and fauna.

It is an outstanding cultural landscape that combines the beauty of a matchless natural setting with a socio-economic structure that dates far back into the past and illustrates ways of life typical of mountainous areas that are disappearing in Europe.

People have developed their way of life, their relationship with the environment and their bonds with others in this area since prehistoric times. In the Middle Ages, an unusual form of economic and social organisation came into being. In both Spain and France, the families, towns, villages, valleys and regions on each side of the Pyrenean chain managed to conquer the 'impassable wall' of the mountains and so were able to engage in trade, make business agreements and forge alliances and cultural ties based on peace and a sense of fellow-feeling. The landscapes we see today are the result of the legacy left to us by our forebears, who worked hard to keep alive a basic system of farming and animal husbandry that would ensure the survival of generations to come and their traditions, rituals, festivals, music and legends. www.pirineosmonteperdido.es Brèche de Roland Photo Archive Sobrarbe County. Pierre Meyer OTAL VALLEY

>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> PRACTICAL INFORMATION ROUTE: Broto - Linás de Broto - Torla - Bujaruelo - Otal Valley.

TYPE OF ROUTE: Linear (return along the same route).

DIFFICULTY LEVEL: On foot - easy.

DURATION: 5 hours; add 3 hours more if you decide to visit the Otal refuge.

DISTANCE: 36 km. San Nicolás de Bujaruelo-Otal refuge: 6,6 km (up)

GRADIENT: By car. Access to the refuge requires climbing a difference in altitude of 250 metres on foot. i STARTING POINT: Broto

>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> COMMENTS This Geo-Route runs through the Ordesa y Monte Perdido National Park, part of the transboundary site Pyrenees-Monte Perdido, declared World Heritage by UNESCO.At certain times of year it is restricted access by private vehicle to "La Pradera de Ordesa", having an alternative bus service.

Information Point of the National Park in Torla. Tel: + 34 974486472

>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> PROFILE GEO-ROUTE

8 9 1500 1 2 3 4 5 6 7 1250 1000

PN 11GEO-ROUTE ofof SobrarbeSobrarbe www.geoparquepirineos.com