Dendrochronology, or tree-ring dating, was introduced into the eastern Mediterranean region for the systematic study of ancient monuments and sites by Prof. Peter Kuniholm (Classical Archaeology, Cornell University; Ph.D. Penn, 1977) in the early 1970's. He was joined shortly thereafter as collaborator by Prof. Cecil L. Striker (Penn, History of Art), who assumed responsibility for the post-Classical, and especially the Byzantine buildings. They worked together in Turkey, Greece, and the former Yugoslavia until 1988. Thereafter, Prof. Striker continued with his own project, concentrating on the dendrochronology of Byzantine and medieval architecture in Greece, the former Yugoslavia, and Albania, and including an eight-year long study of the Heptapyrgion Castle crowning the acropolis of Thessaloniki, Greece.