Tunis is the capital of the Tunisian Republic; Situated on a large Mediterranean gulf, behind the Lake of Tunis and the port of La Goulette (Halq al Wadi), the city extends along the coastal plain and the hills that surround it. At the centre of more modern development (colonial era and post) lies the old medina. Beyond this section lie the suburbs of Carthage, La Marsa, and Sidi Bou Said.