Roman-Period Radiocarbon Chronology of the Great Causeway, Western Wall Tunnels, Jerusalem

This study presents radiocarbon dating results and micro-archaeological analysis of structures related to the Great Causeway exposed in the Western Wall Tunnels excavations in Jerusalem. Stratigraphic sampling for radiocarbon and Fourier Transform Infrared Spectroscopy (FTIR) were applied to various architectural structures and elements. The modeled results place the main structures in the first century CE: the massive yellowish cast dam wall and the channels built within it, between 33 BCE–21 CE, and the magnificent triclinium building, between 26–57 CE. Miqweh 564 and Vault 230 were coated with several layers of plaster, reflecting a prolonged time of use, including plastering after 70 CE. These dates align with the dating of the construction of W2202E, or less probably its replastering, to after the First Jewish Revolt. The study highlights the potential of microarchaeology, stratigraphy and radiocarbon dating in resolving complex urban archaeological issues, even in difficult sections of the calibration curve, such as the first century BCE–first century CE.