At the dawn of the new century the Ukrainian Speleological central part is shown in beige tint on Figure 1, indicating the area Association expedition to Arabika has pushed Krubera above the tree line at approximately 1,800-1,900 m. The highest peak (the Peak of Speleologists) rises to an altitude of 2,705 m. Some (Voronja) to a record-breaking depth of-1,710 m during low altitude ridges, covered with forest, stretch from the central January 2001. For the first time in speleological history the region towards the . world cave depth record has been set outside of Central/ Among the several hundred known in the Arabika massif, Western Europe. This is a remarkable achievement in ultra- some deep caves explored during the 1 980s stand out (indicated by deep exploration and is the greatest single extension since red dots in Figure 1), including the Iljukhina system (-1,240 m), the Arabikskaja system (Kujbyshevskaja-Genrikhova Bezdna; -1,110 1975 in the pursuit of record-breaking depths. The previous m), Dzou Cave (-1,080 m), Moskovskaja Cave (-970 m), Sarma Cave best record set in Lamprechtsofen-Vogelschacht, Austria, has (-700 m) and Cherepash'ja Cave (MN-53; -650 m). The deepest been superseded by some 80 m and the breakthrough com- cave, Krubera (Voronja), is located in the Ortobalagan trough valley, pares favourably with the three earlier attempts, each of some 300 m to the south-east of and 60 m above Kujbyshevskaja which extended the deepest limit an average of 20 m: to - Cave, the main entrance to the Arabikskaja system (Figures 2 & 3). Although Krubera Cave is not connected directly with the Arabikskaja 1,602 m (1989), -1,610 m (1998) and -1,632 m (1998). This system, it is most probably part of a single linked hydrological article describes the speleological potential of the Arabika system. massif, giving a history of exploration and specific details of Figure 2 demonstrates quite strong tectonic control of cave the Krubera cave - including the story of the recent record- development in the plan view. Some segments of the major caves breaking expedition. stretch alongfaults, other sectionstwist within majortectonic blocks and reflect back inside the blocks when intercepted by a . The main branch of the Krubera Cave slews many times and drops Arabika Massif: geological and steeply in depth via vertical pots, separated by short meanders. hydrological features Overall the cave remains within a small tectonic block and does not The Arabika Massif is one of extend beyond the limits of the trough valley (Figure 2). the largest massifs Major springs with individual average discharges of 1 to 4 of the Western m3/s are located at altitudes above sea level ranging from 1 m . (Reproa Spring) to 540 m (Gegsky Vodopad). Submarine springs are also known here, emerging from the floor of the Black Sea at depths of 20-40 m (and probably greater). Some boreholes located

It is located inAbkhasia,a republic which officially be- longs to but holds I., claim to being an independent state. The latter is still a matter of unresolved political contention be- tween Abkhasia and Georgia, hav- along ing resulted in a major conflict during t h e 1993-4. shore of the The massif, with strongly pronounced Black Sea yield glaciokarstic surfaces at elevations ranging be- karst i c grou nd water from tween 1900 and 2500 m, is composed of Lower Creta- depths of 40-280 m below sea level. An outline of the ceous and Upper Jurassic . In the central part of Arabika hyclrogeological structure of the massif and its true speleological the features of age are retained only in a few ridges and potential were revealed in the 1980s when spectacu lar progress was peaks, as well as in patches within the trough valleys,. The core part made in deep cave exploration. Two large-scale dye tracing tests of the massif is composed of Upper Jurassic strata that dip continu- during 198,4 and 1985 proved connections between the major caves ously to the Black Sea shore and disappear below the modern sea and springs (Klimchouk, 1990; see Figure 1). level (Figure 1, section). Geologically, Arabika corresponds to the Tracers injected in the Kujbyshevskaja and Iljukhina caves were large of the sub-Caucasiani (NW-SE) direction, with the detected in Kholodnaja Rechka (1.5 m3/s; 50 m asl) and Reproa (2.5 gently dipping south-western mega-flank (complicated by several m'/sec; 1 m asl) springs along the seashore. The tracer from low-order folds in the same direction) and steeply dipping north- Kujbyshevskaja has also been detected in a borehole which yields eastern flank. The massif is severely tectonifcalty modified, with the groundwater at a depth of 40 m below sea level, located between fault-block structure strongly controlling both cave development these two spri ngs. Th is gave a reason to identify the large centra I karst and groundwater flow systems (Klimchouk, 1990). To the north- hydrological system (No. 1 in Figure 1) with the potential for being west, north-east, and east Arabika is bordered by the deeply incised the deepest in the world at the time, having a vertical range greater canyons of Sandripsh, Gega and rivers. The Iattet separates than 2,300 m. This corresponds with the majority of the south- Arabika from the adjacent Bzybsky Massif, another area with major eastern flank of the major Arabika anticline. speleological prospects in the , including The tracer injected to the Moskovskaja Cave (-970 m) was Snezhnaja-Mezhonogo (-1,370 m) and Pantjukhina (-1,508 m), detected at the Gegsky Vodopad spring, indicating the presence of amongst many other significant caves. a karst hydrological system comprising the north-eastern flank of the Glacial trough valleys formed during the late Pleistocene Arabika anticline (the northern system, No. 2 in Figure 1). No glaciations are the main features of the central part of the Arabika connections have been revealed with yet another major spring, massif (Klimchouk, 1984), with ridges and peaks between them. The Goluboje Ozero in the Bzyb River canyon, although it apparently

C&C Autumn/Winter 2001 35 drains a large area to the southeast of the massif (the hypothetical eastern karst hydrological sys- tem, No. 3 in Figure 1). This outline remains rough and catchment areas of some other considerable springs (in particular those located in town) have not yet been clarified. Further explo- ration of the ar- ea's deep caves and in- vestigation of shaft water flows, with fur- ther tracing ex- periments, will allow greater detail to be added to the over- all picture in the future. posed by poor equipment, tech- niques and the general 'infant' state of Soviet speleol- History of karst studies and cave exploration in Arabika ogy at that time, the Georgian researchers explored several vertical Of the very rich history of karst and speleological investigations in caves to a depth of-250 m and pointed out the considerable depth Arabika we shall mention just a representative sample of the names, potential of the area. In particular, they undertook the first explora- events and circumstances which have the greatest significance in tion of an open-mouthed 60 m shaft in the Ortobalagan trough valley relation to the present day cave explorations. and named it after A. Kruber: the cave that at the very beginning of At the beginning of the 20th century Arabika was visited by the the 21 st century would become the deepest in the world. Forty years famous French speleologist Edward Alfred Martel, who published ago, however, Georgian speleologists were stopped by an impass- several works about the massif (Martel, 1909). During 1 909-10 the able squeeze in a meandering passage which led off from the foot of well-known Russian karst scientist Alexander Kruber, a founder of the entrance shaft. karst science in , performed some field studies in Arabika. He Also during the 1960s a Georgian researcher, Tamaz Kiknadze, published his observations in a series of specific papers (Kruber, made some additional investigations in Arabika, analysed available 1911, 1912a, 1912b) and through several major monographs. data on geology and hydrogeology of the massif, and published a During the subsequent 50 years no special studies were undertaken monographic description (Kiknadze, 1972). Although his ideas on of the karst and caves in the region, although the karst of Arabika was the structure of the karst hydrological systems were not confirmed by referred to in many works dealing with regional geology and later dye tracing experiments, his book was an important summary hydrogeology. of the karst and caves of Arabika. During the early 1960s specific speleological investigations were During the late 1960s and into the 1970s, cavinedubs from started by Georgian researchers (Maruashvili, Tintilozov & Moscow, Crimea and Krasnojarsk carried out several expeditions to Changashvili, 1961, 1962; Maruashvili & Tintilozov, 1963). They the massif, of which the most notable discoveries were Genrikhova recognized the important role of the Quaternary glaciations in karst Bezdna cave in the Ortobalagan trough valley (120 m deep entrance development at Arabika and began to explore caves in the high shaft ending at a squeeze) and the Jubilejnaja, Karrovaja and altitude region of the massif. Despite the obvious limitations im- Akhtiarskaja caves in the northern section. The latter were explored respectively to -260, -200 and -1 60 m. With only six 100 m+ and two 200 m+ deep caves explored by the late 1970s, and none greater than 300 m+, Arabika acquired the some- what paradoxical reputation among cavers - 'Good potential but no deep caves!' Dis- couragement with Arabika was strength- ened, in contrast to the adjacent Bzybsky massif where many 100-300 m deep caves and several 500 m+ caves were under active exploration, including Snezhnaja cave at - 1,380 m. By the late 1970s Arabika had been virtually abandoned by pushing cavers. In 1980 the Kiev Speleological club, led by Alexander Klimchouk, chose Arabika as the main focus for its exploration efforts and implemented a strategy of thorough and systematic 'total' search of the region on an area-by-area basis. This method was par- ticularly successful in the formerly glaciated karst massif, by contrast with the previous 'quick-search' practice, where glacial de- bris blocked most of the open-mouthed shafts. In addition, a 'no dead ends' concept was adopted, which required re-inspection of all the known caves and systematic prob- ing of such common obstacles as boulder chokes and squeezes that had previously obstructed exploration. The Perovsky Spe- leological Club of Moscow led by Vladimir

36 C&C Autumn/Winter 2001 Iljukhin also endorsed these principles and joined exploration activity in Arabika during the same year. The systematic approac quickly led to major discov- eries. The Kiev cavers con- centrated theirefforts in the Ortobalagan trough valley where, among other caves, they pushed Kujby- shevskaja Cave th rough a series of ex- peditions (-450 m in 1981,-700 mini 982, -900 m in 1985, - 1110 mini 986). The main obstacles in this cave were boulder chokes: penetration through just one of these (Ugrjum-Zaval at-700 m) took three years of arduous work. Meanwhile, ex- ploration progressed in the nearby Genrikhova Bezdna Cave, that was even- tually connected with Kujbyshevskaja at - 965 m in 1989. The resultant system has been named Arabikskaja. In Krubera cave, which was supposed to connect with the Arabikskaja system and increase its total depth by 60 m, exploration 3rd sumps. The fourth sump, at -1,240 m, explored for 110 m in progressed slowly because of critically tight meanders between the 1987, remains the end of the system to the present day. For this pots. These meanders required some widening before they could be extreme exploration another outstanding Soviet speleologist, Vladimir passed. The cave was pushed to -340 m during 1982-7 but for a Kisseljov, played one of the leading roles. while exploration was involuntarily suspended. Two 'windows' in Important discoveries made in Arabika by Kiev and Moscow P43, at a depth of 220-250 m, were shown on the made cavers in the early 1980s have attracted many caving clubs from the during the period, but remained unexplored. During this time the formerSovietUnion. Cavers from Leningrad, Sverdlovsk, Krasnojarsk, cave received its second, alternative name Voronja (Crow's Cave) Minsk, Kishinev and Poltava, along with cavers from Belgium, owing to the number of crows nesting in the entrance shaft. Yet Britain, Hungary, Italy and have become involved in the another cave in the same valley, Berchil'skaja Cave, located 150 m explorations at Arabika over subsequent years. All explorations higher than Krubera and 210 m higher that Kujbyshevskaja, had been pushed by Kiev and Moldavian cavers down through a vertical boulder choke which ex- tended almost continuously from the bottom of the upper 60 m deep shaft to the current end at -500 m. Cavers of Perovsky club, based mainly in the upstream part of the Central trough valley, invested most of th e i r efforts inpushingPerovskaja Cave, which was later re-named after an outstanding Soviet speleologist Vladimir Iljukhin who was accidentally killed by a car in the town of , after making it down from Arabika fol lowi ng the 1992 expedition. Club members reached the first sump at-950m in 1984 and spent huge efforts during the subsequent years negotiating their way through a series of three sumps and the 'dry' sections be- tween them - including a 230 m deep section between the 2nd and KRUBERA (VORONJA) CAVE Arabika massif, Western Caucasus during the 1980s were closely co-ordinated, with advanced planning and the assignment of specific areas for each group Compiled by Ju. Timoshevskaja and A.Klimchouk, Based on survey data of 1986 and 1999-2001 provided by: during the coming year. Results were reported at the regular Arabika conferences held in Kiev following each field sea- Ju. Timoshevskaja, A. Kovalev son. By the end of the decade some thirty six 100 m+ deep Ju. Kasjan, O. Rjazanova A. Romanenko, A. Karpechenko caves had been explored, including seven at 500 m+. G. Rjabukhin, N. Jablokova During 1 984-5 two large-scale dye tracing experiments A. Morena Rioxa, E. Ogando Lastra were conducted at Arabika, for which three different tracers S. Garsia Dils, B. Tourte were used to trace water flows down shafts in Kujbyshevskaja, O. Klimchouk, V.Galas lljukhina and Moskovskaja caves. All the known springs and boreholes were monitored around the massif. These experiments proved hydrological links between - both Kujbyshevskaja & lljukhina caves and the major springs

on the sea- shore over a dis- tance of 14-20 km as the crow flies and a vertical range in excess of 2,300 m. Clearly, the decade of the 1980s resulted in dramatic progress for speleologi- cal exploration at Arabika and revealed its true depth potential (Klimchouk, 1990, 1991). Unfortunately, the political and ethnic conflict in Abkhasia during 1 992-4 resulted in instability and border problems, which have continued over subsequent years. This resulted in a suspension of speleological explorations in Arabika. Although some small groups of cavers occasionally visited the massif during the period, the planning and realization of large, serious expeditions became unfeasible. However, stabilization of the situation in 1997 has since enabled a renewal of exploration

effort to take place in the region.

Recent explorations in Arabika: breakthrough in Krubera Cave In 1998 the CAVEX team, consisting mainly of Kiev and Moscow cavers, made a breakthrough in Dzou Cave in the northern part of Arabika, previously ex- plored by Vladimir Kisseljov and the French team from Lyon to a depth of 700 m. The expeditions of 1998 and 1999 resulted in the discovery of an extensive hori- zontal trunk river collector at the lowest level and succeeded in pushing the cave to -1,080 m. During August 1999 the Ukrainian Speleo- logical Association expedition (including cavers Uzhghorod and Dnepropetrovsk), led by Yury Kasjan, re-commenced work in the Ortobalagan trough valley, the Arabikskaja system and Krubera. The main target was to find a connection between Krubera and Kujbyshevskaja caves, which would increase the total depth of the system by 60 m. In Krubera the team checked the two 'windows' in the walls of P43 (-220 - 250 m) - unexplored since the 1 980s - and found continuations from both. The lower window led to a new branch that appeared to head towards Kujbyshevskaja, but eventually missed it and ended in a chamber, Non-Kujbyshevskaja, at -490 m. The upper window, however, opened to another branch which was explored to -750 m during the 1 999 expedition. Alexey Zhdanovich from Uzhghorod was instrumental in this breakthrough and during the subsequent explorations. The Ukr.S.A. expedition of 2000 ran in two stages, both led by Yury Kasjan. During the first stage (August), in which cavers from Poltava, Uzhghorod, Kiev, Kotel'va and Novaja Kakhovka participated, the main branch was explored and surveyed to—121 5 m. For the second stage the MTDE team, composed of six cavers from (Sergio Garsia Dils de la Vega, Vilafranca Javier la Pera, Enrico Ogando Lastra, Juan Alberto Martin Otero, Alfredo Morena Rioxa & Ramos Ignacio de Rafael)

38 C&C Autumn/Winter 2001 and two cavers from France (Bernard millennium also played its part and we decided to Tourte and Olivie Ubiergo), joined organize the next expedition to Krubera cave during the Yury Kasjan & Denis Provalov to winter: a severe time at Arabika in terms of access and surface continue with the exploration. They conditions. Among rational reasons for this decision was the dread reached a depth of -1,410 m in a of sudden flooding at great depth which might be expected during branch which seemed to lose the the summer, should the cave enter the hypothetical major river draught, ending at a squeeze. Whilst as- collector. cending from the very last trip to the bottom, The core of the winter expedition, organized under the banner of Yury Kasjan found a window in the wall of a pot the Ukrainian Speleological Association, was composed of mem- at -1,340 m, which promised a continuation bers from CAVEX (Cave Exploration) Association, a strong group of dedicated Kiev and Moscow cavers with extensive experience of There are many aspects, some of deep cave expeditions during winter conditions. which lie beyond the scope of rational thinking, which experienced cavers The winter expedition 2000-2001 weigh up when assessing the pros- The expedition began on 25th December and consisted of eleven pects for future exploration. During members: Yury Kasjan (leader), Julia Timoshevskaja & Anatolij the fall of 2000 we clearly heard Povjakalo-fromPoltava, ;OlegKlimchouk, NikolajSolovjov, 'the Call of the Abyss' and sensed Sergej Zubkov-from Kiev, Ukraine; Vitalij Galas-from Uzhghorod, the smell of extreme depth. In what Ukraine; Konstantin Moukhin, Denis Provalov & Dmitry Skljarenko was a mixture of knowledge of the - from Moscow, Russia; and llija Zharkov - a former Sverdlovsk general potential of Arabika, his- caver, currently based in Pennsylvania, USA. torical events, impetus of recent ex- On 27th December the expedition members arrived at Sochi, the plorations, excellent team resources main city on the Russian side and crossed the Abkhasian border. at our disposal and other more mysteri- Next day a helicopter from , the Abkhasian capital, brought ous feelings, we decided not to wait until all the members and their equipment to the Ortobalagan trough the next summer. Probably the turn of the valley in Arabika. Work stopping at the head of a new pitch. This news, delivered to the started in underground camp at -1,215 m on the morning of 5lh January, the cave brought great excitement and elation to all its inhabitants. While the on 29th next two pairs of explorers descended to push the cave further, Denis D e - Provalov returned to the surface to broadcast the news on 6th January c e m - to civilization via a mobile 'phone. b e r The pitch at -1,680 m turned out to be the final one of the and expedition. It led to a big chamber with a boulder choke at the far during end: the deepest point reached so far (-1,710 m). A 'window' above t h e the choke leads to a series of smal ler breakdown chambers, but has first so far yielded no continuation. Four other expedition members have day also visited the lowest area for additional inspection, surveying work t h e and de-rigging of the bottom-most region. The big chamber has been route named the Chamber of Soviet Speleologists, in appreciation of the was long and hard journey undertaken by many generations of cave rigged as explorers from the former Soviet Union in fulfilling this remarkable far as first achievement. camp at -500 On the night of 9th January all expedition members and equip- m, where sev- ment were back on the surface: the next day was time for recovery! eral tackle bags were By 11th January everything was ready for the helicopter evacuation stockpiled. Such a as pre-arranged for this date. However, the helicopter did not arrive, quick start was owing to the weather conditions in Sukhumi. possible owing The time had come for the pay back after such smooth efficiency to preparations in the cave ... During the night the weather in Arabika deteriorated dramatically and the next day the team bid farewell to iats hopes of the imminentarrival of a helicopter, with strong wind, heavy snowfall, and low visibility. The poor weather continued through the next n ight and a telephone forecast for the coming few days predicted a continuation of unfavourable conditions. Eventually, expedition members decided to leave all their equipment, bar light camping stuff, and force a way down that on foot. It was a risky venture owing h a d to the potential hazard of avalanches been en route to the tree line, some 5 km madeduring distant and followinga long traverse. the previous expeditions, The team, split into two groups, when ropes had been was making its way with great dif- stored at the top of the ficulty through the heavy snow, main pitches. By 31st De- about midway along the traverse, cember the route was when a large avalanche crossed rigged as deep as-850 m, their path, just in front of the first with many bags being i group. The tumbling snow caught transported to the limit. and buried the lead man, Anatolij Meanwhile, a special team Povjakalo. Anatolij was immediately was enlarging three squeezes1 dugout, shaken but safe! The night was in the upper reaches of the cave spent in a forest and by the afternoon of ,h (first breached by Kiev cavers in the nextday, 14 January, the team reached the 1980s, but still remaining barely an ascending group in the Sandripsh can- passable) to a degree which would yon, led by a local guide, Vatik Vartanjan, and allow easier passage for many cavers a caver from Brest, Sergej Krasko. Sergej had and bags as they passed back and forth arrived the previous day by air to co-ordinate an though them. anticipated rescue operation. It was a happy meeting For midnight on 31st December the expedition mem- and end to the active part of the expedition. bers gathered on the surface in a small cave not far from the camp. On 1 6th January the weather had improved sufficiently to allow This had been converted into a kitchen and dining room, to celebrate a quick helicopter flight to Arabika for removing the stockpiled the New Year at the beginning of the new century and millennium. equipment. In both Kiev and Moscow expedition members were Everything and everyone was mentally and physically prepared for greeted by orchestras, champagne, flowers, caving friends, reporters achieving the new world depth record. and television crews! On 1st January the work in the cave continued: by the following day an advance group had set up the main camp at -1,215 m with Techniques and equipment everyone based underground. Each expedition member was as- The exploration was undertaken using standard European single- signed specific tasks to be carried out for this assault. On 3rd January rope techniques and equipment. The total rigging required over the advance group reached the window at -1,340 m and began the 2,000 m of rope and some 300 anchors. Almost everywhere ropes original exploration. The right to descend the first new pitch of the were rigged away from the water flow and running trickles, so that expedition was given to the youngest member, Anatolij Povjakalo, no waterproof suits were required to work in the cave. on his 18lh birthday. By the end of the day a depth of approximately During the winter expedition two underground camps were used: -1,450 m had been attained. at-500 m and -1,215 m, respectively. The former camp, located at The previous depth record set in Lamprechtsofen-Vogelschacht the bottom of P152, is subject to the hazard of rock fall. was broken during the night of 4-5th January by the pair Moukhin & For further work in the lowest regions a camp can be Zharkov. They descended several new pitches, including the im- set up in the Chamber of Soviet Speleologists at pressive P49 which passed through almost completely black lime- -1,710 m, although the possibility of local flood- stone1, and reached a very satisfactory depth of about -1,680 m, ing owing to the boulder choke constriction-

C&C Autumn/Winter 2001 should be considered. The camp at -1,215 m was kitted out to References accommodate eight cavers. Exploration of the lower part of the cave Kiknadze, T. Z. 1972. proceeded continuously in two shifts through the efforts of four pairs Karst of the Arabika massif. of cavers. All expedition members had the chance to work in the Tbilisi: lowest region below -1,600 m, and a total of nine of attained the very Metzniereba, 245 pp bottom. (in Russian) Klimchouk, A. B. 1984. On Topographic survey and depth estimate impact of the late Quater- nary glaciations on the karst The topographic survey of the cave was performed using Suunto and development of the Arabika massif Soviet 'geological' compasses and clinometers. In addition, two (Caucasus). Izvestia VGO (Lenin- Casio watch altimeters were used as control on the depth achieved grad), 116(2), 165-170 (inRussian) by repeated incremental measurements. The depth of the lowest Klimchouk, A. B. 1990. Karst circula- tion systems of the Arabika massif. point in the cave was 1,720 m according to the altimeters, but 1,710 Peschery (Caves), inter-university m according to the clinometer measurements. The latter figure has scientific transactions, Perm: eventually been taken as the 'official' reading. In general, the Perm University, 6-16 (in Russian) resultant plan and elevation (Figure 4) correspond to BCRA Grade 4 Klimchouk, A. 1991. Le grotte del standards. massiccio di Arabika. La Rivista del CM, 112(1), 37-47 In September 2000 the MTDE team took independent depth Kruber, A. A. 1911. Karabi-Yuajla and the measurements as far as the -1,410 m point using two accurate Arabika massif Zemlevedenie (Moscow), altimeters, and found a concordance to within 5 m of the depth 18 (3) (in Russian) readings previously determined by the clinometer survey. Kruber. A. A. 1912a. The voyage to Arabika. Estestviznanie i geografia (in Russian) Brief notes on the cave and further prospects Kruber, A. A. 1912b. From observations of karst in the vicinity of Gagra and Karabi- Krubera Cave is developed in the thickly-bedded and massive Upper Yuajla. Zemlevedenie (Moscow). 19 (1- Jurassic limestones, in the fold zone of the Berchil'sky anticline. The 2) (in Russian) limestones become increasingly sandy, commencing at a depth of Martel, E. A. 1909. La Cote d'Azur Russe about 300 m, with maximum sand content evident through the depth (Riviera du Caucase). Ch. XVI: La massif interval of 400-600 m, a feature previously noted in the adjacent de I'Arabika, Paris Maruashvili, L. I., Tintilozov, Z. K. & Changashvili, Kujbyshevskaja Cave. G. Z. 1961. The results of speleological ex- The main branch of Krubera Cave descends steeply in vertical plorations carried out in I960 on the pitches, separated by short meanders, while shifting slightly towards Arabika limestone massif. Izvestia AN the southern slope of the anticline. Apart from the 'non- GSSR (Tbilisi), XXVI (5) (in Russian) Kujbyshevskaja' branch, which stretches for almost 500 m to the Maruashvili, L. I., Tintilozov, Z. K. & , Changashvili, G. Z. 1962. Karst and ] north-west, the cave is formed within quite a small area (400 m by ancient glaciation in Arabika. Ab- 400 m), remaining within a small tectonic block and not extending stracts of papers of the 2nd scientific beyond the southern ridge of the trough valley. session of speleologists. Tbilisi: AN Through both the degree of morphological development and its GSSR (in Russian) Maruashvili, L. I & Tintilozov, Z. K. 1963. hydrological system the cave is subservient to the adjacent The results of the recent speleological ex- Kujbyshevskaja Cave. A small water flow (up to 1 l/sec) appears in plorations in the karstic belt of the the cave at a depth of about 340 m. This flow disappears and Western Georgia in 1957-1960. reappears at various levels, but never increases significantly. Zemlevedenie (Moscow), nov. ser. VI (in Russian) By its present bottom-most point at -1,710 m (530 m above sea level) the cave neither enters a master river passage nor shows any signs of considerable flooding, which would indicate close proxim- 1 This pitch was named af- ity to the base level of a main 'collector'. These features, together ter Kim Cunningham, the with the previously proven connection of the Arabikskaja system to well-known American cave large springs on the shore of the Black Sea, suggest a further potential scientist - an explorer of for deepening the cave by at least 150-200 m (conservative estimate) Lechuguilla cave and a or as much as 300-350 m (optimistic estimate!) good friend of the Ukrain- Equally realistic is the possibility for connecting caves with ian speleologists entrances at higher elevations into the Krubera Cave main system. who died about The best prospects can be found in the nearby Berchil'skaja Cave (- week before the 500 m), the entrance of which is some 1 50 m above, and Martel's start of the expe- Cave, located some 80 m higher up. Hence the future possibility of dition. gaining a 2,000 m+ system in the area is exceptionally good. The Ukrainian Speleological Association and CAVEX Associa- tion will continue determined and regular efforts over the next few years, during both the summer and winter periods, in order to fully explore Krubera and the other caves of the Ortobalagan trough valleys, with the ultimate goal of discovering and exploring the first 2,000 m+ cave on .

Acknowledgements The BASK and Alpindustria companies, based in Moscow, donated equipment to the winter expedition. The Canon branch office in Moscow sponsored us with video and photographic cameras. We sincerely thank them all for this help.