Porto Palermo Castle, Stone castle on Porto Palermo peninsula, Albania.

Porto Palermo Castle is a three-sided fortress with three large gun bastions at its corners and an open terrace to the south. Inside, a hexagonal central chamber with a domed ceiling and six large pillars gives access to all rooms and terraces; soldiers stayed in rectangular rooms. The site was originally a small island, later joined to the mainland by landfill.

An inscription above the entrance records that the castle was built in 1804 by French engineers for Ali Pasha of Tepelena, who worried about the open coastal flank of his pashalik. In 1803 he had offered the fort and port to the Royal Navy, when it held only four or five cannon. William Martin Leake found a garrison of ten men with two four-pounders; François Pouqueville visited in 1806.

The castle's Albanian name is Kalaja e Porto Palermos. Greek poet Ioannis Vilaras, a member of Ali Pasha's court, praised its construction in verse. A 1921 designation called it the "Venetian castle" of Porto Palermo, a name that persisted despite the fort's Ottoman origin.

The site is accessible from the road, and visitors should wear sturdy shoes since the ground is uneven and some stairs are steep. There is limited shade, so it is best to visit early or late in the day during warm weather.

During the Communist era, the military used the grounds as a secret submarine base, with tunnels carved into the surrounding rock. These underground structures are still partially visible today and reveal a completely different use of the fortress.