Koprinka Reservoir

Koprinka Reservoir is a water storage basin in Stara Zagora Province in Bulgaria, built with several arms and bays that extend across a hilly landscape. The reservoir sits at an elevation of roughly 390 meters (1280 feet) and reaches depths between 44 and 78 meters (144–256 feet) depending on the contour of the valley floor.

The dam was completed in 1955 and flooded the ancient Thracian city of Seuthopolis, which had once been the capital of the Odrysian kingdom. Archaeologists recovered artifacts from the site before the valley filled with water.

The Regional Museum of History preserves numerous archaeological artifacts recovered from Seuthopolis before the reservoir filled the area.

The basin supplies water for farming and industry in the region and generates electricity through a turbine at the dam. Visitors find opportunities for recreation and boating along stretches of the shore, though access varies by section.

An architectural design proposes building a circular wall around the submerged ruins of Seuthopolis so that visitors could reach the site by boat. This project would partially expose the ancient city center below the water level and make it accessible on foot.