Famagusta is one of the most historically layered cities in the eastern Mediterranean — a walled medieval city on the eastern coast of Cyprus that has been Lusignan, Venetian, and Ottoman in turn, and that contains the most impressive ensemble of Gothic architecture anywhere in the region outside of France. Walking through the old town is a slightly disorienting experience: Gothic cathedral arches rise above the skyline with Ottoman minarets added later, Venetian palace facades crumble beside Byzantine ruins, and the whole thing is enclosed by walls three kilometres long and in places nine metres thick, built as if the Venetians expected the Ottomans to come — which, in 1571, they did.
The city is officially part of Cyprus but has been under Turkish Cypriot administration since the 1974 division of the island. The Greek Cypriot residents who left in 1974 have not been able to return; the city they left behind, including the abandoned resort suburb of Varosha, remains a sensitive political subject. For the traveller, this context is part of the place — you can see Varosha's ghost hotels from the beach to the south, fenced off and slowly disintegrating.
The Lala Mustafa Pasha Mosque, formerly the Cathedral of Saint Nicholas, is the centrepiece of the old town — a 14th-century Gothic cathedral converted to mosque use after the Ottoman conquest, its western facade so French Gothic in inspiration that it looks like a piece of Reims teleported to Cyprus. Beside it, the Palazzo del Provveditore — the ruined Venetian governor's palace — frames one side of the square. The Othello Castle stands at the harbour; the walls themselves are more or less intact and walkable.
Famagusta takes a day to explore properly: the old town on foot in the morning, Othello Castle in the early afternoon, and the ruins of Salamis (ancient Greek city, 8km north) as a half-day add-on. The city is small enough to walk entirely, and even in summer not overwhelmingly crowded.