The main town is located inland in a flat valley between the two mountain ranges of Serra d'Irta and Serra de les Talaies. There is no river in the valley; instead the water emerges in natural ponds known as basses.
The landmark of the town is the Esglèsia de Sant Joan Baptista (Church of Saint John the Baptist), built in 1736–1766, with a large dome, a noteworthy Baroque portal, and a 68-metre-high tower, which is visible from many miles away.
Its castle occupied a strong position for the control of the routes along the Mediterranean coast. Here stood a Moorish castle (the name of the town derives from Arabic al-qalat = "the castle") that was captured by James I of Aragon in 1234, who also resettled the place with Christian villagers.
In contemporary times the economy of the town is devoted mainly to tourism, with several beaches and a busy marina at the villages located on the coast, Alcossebre, Capicorb and Les Fonts.