Nafpaktos Castle, Medieval fortress in Nafpaktos, Greece

Nafpaktos Castle is a fortress on the southern slope of a 200-metre hill above the Corinthian Gulf, covering about 175,000 square metres. Its outer walls run roughly 2,250 metres and enclose an upper circuit with the acropolis, or Its Kale, and a lower circuit around the port. Four cross-walls divide the two circuits, and the second circuit holds the 19th-century single-aisle church of the Prophet Elias.

The castle originated in ancient times as a naval station for Athens during the Peloponnesian War before coming under Venetian and then Ottoman control. This succession of rulers over several centuries shaped the fortress into the structure seen today.

The fortress displays architectural features from multiple periods, with Byzantine walls, Venetian gates, and later Ottoman modifications visible throughout the fortification. Walking through the structure reveals how each era left its mark on the defensive design.

The walls run from the hilltop down to the sea, so the climb between the upper and lower circuits is long and the ground is uneven. The upper circuit has two cross-walls dividing it into three zones, and the north side is the most ruined. Allow time to walk the full 2,250 metres of outer wall.

The castle's walls reuse stone from the ancient fortifications and older city buildings, so blocks from the classical town are set into the medieval masonry. The Venetians also replaced square towers with truncated-cone bastions and added sloping scarps to resist artillery fire.