Abstract Philippi, a small Greek and then Roman town in Northern Greece, became a flourishing pilgrimage center in the fourth century, commemorating the first Christian community in Europe established by St. Paul. After the sixth century, impressive churches and other buildings of the town were turned into ruins, currently registered in the UNESCO World Heritage. The reasons and timing of the demise of the town are unclear, and several scenarios have been proposed to explain them. Analysis of excavation data indicates no signs of invasion by Slavs or Avars, but sitewide destruction, which can be assigned to a major unrecorded earthquake that occurred probably within approximately 15 yr after 615, as numismatic data (hiatus in coin circulation) reveal. This result is important because Philippi is in a low-seismicity region, whereas an earthquake alone cannot easily explain the demise of a town with a millennium-long history. However, it was found that the destructive earthquake had produced an up to 10 m drop in a karstic spring feeding a low-gradient aqueduct, depriving Philippi of a main infrastructure of a Roman and Byzantine town, especially of a pilgrimage center. This, in combination with the overall sociopolitical situation, hindered the town’s postseismic recovery. The destruction pattern and extent, as well as the structural characteristics of the destroyed buildings, testify to a strong earthquake of intensity IX or X (MMS) from a nearby source. Two nearby known active normal faults are candidates for the earthquake source, but the Xanthi fault, well marked in the topography, and especially its continuation offshore, is more likely, because it runs mid-distance (about 20 km) from Philippi and the Town of Thasos, another site for which seismic damage at the same period was claimed.
Stathis C. Stiros (Fri,) studied this question.