Unveiling the past through dendrochronology: Late Roman architecture in İstanbul

Abstract

Excavations around the main train station at Haydarpaşa in the Kadıköy district on the Asian side of İstanbul uncovered a T-shaped structure previously attributed to the Roman period. Dendrochronological analysis of six oak (Quercus sect. Quercus) beams from the structure revealed a surprisingly early construction date of 369CE, much earlier than previously assumed. Short tree-ring series were successfully integrated to build a robust chronology and were cross-dated against the established Yenikapı oak master chronology. These findings not only provide the first firm evidence for a Late Roman building in this part of İstanbul but also strengthen the Late Roman and Early Byzantine dendrochronological framework for Türkiye. A mean chronology constructed for Haydarpaşa, termed HYP, was used to date another set of samples from the excavation area in Aksaray, on the European side of İstanbul. There, wooden samples collected from the basement of a structure were dated to 340CE, and another mean chronology, named SMI24, was developed for this site. The results of this study highlight the potential of integrating archaeological excavations and dendrochronology as a powerful approach to uncovering previously unrecognized aspects of early urban history.