A STUDY ON THE BUILDING TECHNIQUES AND MATERIALS IN THE LATE ANTIQUE AND BYZANTINE FORTIFICATIONS IN ANATOLIA: ANCYRA AND NICAEA A THESIS SUBMITTED TO THE GRADUATE SCHOOL OF NATURAL AND APPLIED SCIENCES OF MIDDLE EAST TECHNICAL UNIVERSITY BY MERCAN YAVUZATMACA IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE IN CONSERVATION OF CULTURAL HERITAGE IN ARCHITECTURE DECEMBER 2016 Approval of the thesis: A STUDY ON THE BUILDING TECHNIQUES AND MATERIALS IN THE LATE ANTIQUE AND BYZANTINE FORTIFICATIONS IN ANATOLIA: ANCYRA AND NICAEA submitted by MERCAN YAVUZATMACA in partial fulfillment of the requirements for the degree of Master of Science in Conservation of Cultural Heritage in Architecture Department, Middle East Technical University by, Prof. Dr. Gülbin Dural Ünver Dean, Graduate School of Natural and Applied Sciences ____________________ Prof. Dr. Elvan Altan Head of Department, Architecture _____________________ Assoc. Prof. Dr. Ufuk Serin Supervisor, Architecture Dept., METU _____________________ Examining Committee Members: Prof. Dr. Suna Güven Architecture Department, METU ______________________ Assoc. Prof. Dr. Ufuk Serin Architecture Department, METU ______________________ Prof. Dr. Ayşıl Tükel Yavuz Architecture Department, METU. ______________________ Assoc. Prof. Dr. Namık Erkal Architecture Department, TED Uni. ______________________ Assist. Prof. Dr. Çiğdem Atakuman Settlement Archeology Dept., METU ______________________ Date: 02.12.2016 I hereby declare that all information in this document has been obtained and presented in accordance with academic rules and ethical conduct. I also declare that, as required by these rules and conduct, I have fully cited and referenced all material and results that are not original to this work. Name, Last name: Mercan YAVUZATMACA Signature : iv ABSTRACT A STUDY ON THE BUILDING TECHNIQUES AND MATERIALS IN THE LATE ANTIQUE AND BYZANTINE FORTIFICATIONS IN ANATOLIA: ANCYRA AND NICAEA Yavuzatmaca, Mercan M.Sc. in Conservation of Cultural Heritage, Department of Architecture Supervisor: Assoc. Prof. Dr. Ufuk Serin December 2016, 221 pages This research aims to investigate building techniques and materials in the Late Antique and Byzantine fortifications of Anatolia through the selected case studies of Ancyra/Ankara and Nicaea/Iznik. The majority of Late Antique and Byzantine fortifications in Anatolia are distinguished by ashlar masonry, including quantities of spolia, with alternating courses of brick. The frequent appearance of brick, in combination with more-or-less regularly cut blocks or spolia, in the buildings and fortifications of Anatolia from the Late Roman through to the Byzantine periods (particularly from the ninth century onwards) creates difficulties in offering a precise dating for these structures. The citadel of Ankara, in terms of construction technique and materials, finds one of its closest parallels in the fortifications of Iznik. The major modification to the walls of Iznik, originally built in the third century AD, is attributed to Michael III, or precisely to the year 858 by the inscriptions. The eighth and ninth century phases of the walls of Iznik are characterized by rich quantities of spolia alternating with bands of brick. v Similarly, the rebuilding of the inner circuit of the Ankara fortifications, built of large blocks of spolia up to a height of eight-to-ten meters, capped above by alternating courses of brick and rubble stone, is attributed to the year 859. The rebuilding of the walls of both Ankara and Iznik were included in a large-scale program of fortification by the Emperor Michael III (842-867). A close examination of these two fortifications will help us understand the development of the variations in ashlar masonry and spolia, in combination with brick, and shed light on dating and restitution issues, assisting in determining appropriate conservation approaches, in other Late Antique and Byzantine fortifications in Anatolia. Keywords: Late Antique and Byzantine Fortifications, Ancyra, Nicaea, Construction Techniques, Building Materials. vi ÖZ ANADOLU’DAKİ GEÇ ANTİK VE BİZANS DÖNEMİ SURLARININ YAPIM TEKNİĞİ VE MALZEME BAKIMINDAN İNCELENMESİ: ANKARA VE İZNİK Yavuzatmaca, Mercan Yüksek Lisans, Kültürel Mirası Koruma, Mimarlık Bölümü Tez Yöneticisi: Doç. Dr. Ufuk Serin Aralık 2016, 221 sayfa Bu çalışma Anadolu’da bulunan Geç Antik ve Bizans dönemi surlarını yapım teknikleri ve malzemelerini bakımından Ankara ve Iznik kentleri aracılığıyla incelemeyi amaçlamaktadır. Anadolu’da bulunan Geç Antik ve Bizans dönemi surlarının büyük bir kısmı bol miktarda devşirme malzeme içeren kesme taşların tuğla sıralarıyla birlikte yaptığı almaşık dizilim ile diğerlerinden ayırt edilmektedirler. Kesme blok taşlarla ya da devşirme malzemelerle birlikte tuğla kullanımı Geç Roma döneminden Bizans dönemine kadar (özellikle dokuzuncu yüzyıldan itibaren) Anadolu’nun binalarında ve sur duvarlarında sıklıkla görülmektedir ve bu nedenle bu yapılar için kesin bir tarihleme yapmak zorlaşmaktadır. Ankara kalesine yapım tekniği ve malzeme bakımından en yakın sur duvarı Iznik surlarıdır. Iznik surları üçüncü yüzyılda inşa edilmiştir ve Michael III döneminde ya da yazıtlarda yazan kesin tarihi ile 858 yılında önemli bir değişim geçirmiştir. Iznik surları sekizinci ve dokuzuncu yüzyıllarda bol miktarda devşirme malzeme ile birlikte tuğla sıralarının almaşık dizilimi ile farklılık göstermektedir. vii Benzer bir şekilde, Ankara kalesi iç sur duvarında sekiz ile on metre yüksekliğe kadar devşirme malzemelerin kullanımı ve üst kısımlarında bulunan moloz taş ile tuğla sıralarının almaşık dizilimi ise 859 yılında yapılmış olan bir yeniden inşa dönemine atfedilmektedir. Ankara ve Iznik sur duvarlarının yeniden inşa edilmesi İmparator Michael III tarafından yapılmış olan büyük çaptaki sur çalışmalarına dahil edilmektedir. Bu iki sur duvarının yakından incelenmesi, tuğla ile birlikte devşirme malzeme ve kesme taş kullanımı çeşitliliğinin gelişimini anlamamıza yardımcı olacak, Anadolu’daki diğer Geç Antik ve Bizans dönemi surları için uygun koruma yaklaşımlarının belirlenmesinde ve tarihleme ve restitüsyon konularında ışık tutacaktır. Anahtar Kelimeler: Geç Antik ve Bizans Dönemi Surları, Ankara, Iznik, Yapım Teknikleri, Yapı Malzemesi. viii To my beloved family and to all children of the world, whose right to life has been taken away. ix ACKNOWLEDGEMENT Many people have contributed to the thesis study and I would like to express my thanks to all of them. I would like to express my sincere gratitude and admiration to my advisor Assoc. Prof. Ufuk Serin, for her continuous support. Her patience, guidance, motivation and seminal criticism helped me throughout the time of researching and writing of this thesis. She became the source of inspiration for me to study the Late Antique and Byzantine periods. It was a great opportunity for me to know her as she has made important contributions to my academic life. I also would like to thank to rest of my thesis committee members, Prof. Dr. Ayşıl Tükel Yavuz, Prof. Dr. Suna Güven, Assoc. Prof. Dr. Namık Erkal and Assist. Prof. Dr. Çiğdem Atakuman, who made important contributions to my thesis, brought insightful and motivating comments and encouraged me to continue my works in this subject. I must express my very deepest gratitude to my cherished friends Günce Uzgören, Tuğba Sağıroğlu, Başak Kalfa and Ayşegül Akgün, who have provided the greatest support in finalizing my thesis work and have stood at my side. I thank to my fellow office colleagues Betül Kurtuluş, Meltem Erdil and Deniz Üçer for their endless support and concern. I thank also Filiz Diri Akyıldız, Öncü Güney, Nehir Akgün, Meltem Çetiner, Gökhan Okumuş, Gülnur Güler, Nilüfer Kızılkaya, Gonca Tunçbilek, Emine Çiğdem Asrav, Özgün Özçakır, Aynur Uluç and Neris Parlak for their support and tolerance in overcoming this difficult period. I owe many thanks also to Jonathan Smith for the final revision of the English text. I am very thankful to my dormitory mates Şükran Okur, Emine Aytekin, Günseli Durmaz, İrem Hafız, Öncü Özalp, Shabnam Mehrtash and Seden Demirtaş who revitalized me with their patience and psychological supports. I would like to thank to my friends Betül Özcan, Merve Nur Oymak, Mehtap Kaya, Esra Koç, E. Merve Cezlan, Müzeyyen Dindar, Mevlide Şan, Ayfer Yılmaz, Emel Durmaz, Serkan Yavuz and Fatma Dikçal, who did their best to support me and adorned my life even though x they were not near me when I was living in Ankara. I would like to thank to my dear niece H. İbrahim Korurer who stood by me for days during the field works in Iznik and Kadir Balı, who helped me to obtain some visuals about Iznik. I cannot finish this part without expressing my gratitude to Assist. Prof. Dr. M. Oğuz Sinemillioğlu, who has inspired me to make an academic career and has become a source of motivation with his trust in me since the years of my licentiate education. I would also like to thank to the Head of Department of Architecture, my professors in the Graduate Program in Conservation of Cultural Heritage and my colleagues. In addition, I must give thanks to Rüstem Taşman, Mücahit Erdem and Hamdi Kömürcü for bringing happiness and increasing our eagerness to work with their cheerfulness. Finally, I must express my very profound gratitude to my dear father Salman Yavuzatmaca, my mother Elif Yavuzatmaca and all members of my large family who throughout my life have always been with me with their love and supports and made me believe in myself when I felt powerless