Allianoi

Allianoi is a remarkably well-preserved Roman thermal spa complex situated about 18 kilometers northeast of Pergamon, likely at its peak in the 2nd century AD — possibly under Emperor Hadrian. Excavations from the 1990s onwards uncovered paved streets, a bathhouse with mosaic floors, and an aqueduct in near-intact condition. Despite a years-long legal battle by heritage authorities in İzmir, the site was ultimately flooded in January 2011 by the Yortanli reservoir, a decision that drew international condemnation from archaeologists. Today Allianoi lies submerged, with remnants of its walls occasionally visible at low water — a haunting reminder of one of Turkey's most contentious modern heritage disputes.