The Tower of Apollonia or Tower of Eleftheres (Greek: Πύργος Απολλωνίας or Πύργος Ελευθερών) stands on the coastal hill 27 kilometres (17 mi) east of the Strymon River estuary in the Thracian Sea. The small settlement of Pyrgos, some 700 m northeast of the tower, is named after it.