Tallinn is the capital city of Estonia, located in northern Estonia on the Gulf of Finland. It has a population of over 400,000 people. Tallinn was founded in the early 13th century by the Danes and came under the rule of Denmark, Sweden, Germany, and Russia throughout history. The well-preserved Old Town of Tallinn is a UNESCO World Heritage site consisting of the upper and lower towns. Important landmarks include Toompea Castle hill and Tall Hermann tower in the upper town, and the 15th century Town Hall square in the lower town.