Founded as a French colonial settlement in the 17th century, Saint-Louis was urbanised in the mid-19th century. It was the capital of Senegal from 1872 to 1957 and played an important cultural and economic role in the whole of West Africa. The location of the town on an island at the mouth of the Senegal River, its regular town plan, the system of quays, and the characteristic colonial architecture give Saint-Louis its distinctive appearance and identity.

Źródło: World Heritage Convention
http://whc.unesco.org/en/list/956