The southern coast of the Gulf of Finland was inhabited by Finno-Ugric tribes as early as the 2nd millennium BC.

An excerpt from the article 27 facts about Tallinn

The first mention of Tallinn appeared in the work of the Almoravid (soldier monk) cartographer Muhammad al-Idrisi. In 1154, he drew up a map on which a city appeared, described as a fortress, called Kaluria.