Tallinn is the capital, the primate and most populous city of Estonia. Situated on a bay in north Estonia, on the shore of the Gulf of Finlan…Tallinn is the capital, the primate and most populous city of Estonia. Situated on a bay in north Estonia, on the shore of the Gulf of Finland of the Baltic Sea, Tallinn has a population of about 457,000 and administratively lies in the Harju maakond. Tallinn is the main governmental, financial, industrial, and cultural centre of Estonia. It is located 187 km northwest of the country's second largest city, Tartu; however, only 80 km south of Helsinki, Finland, also 320 km west of Saint Petersburg, Russia, 300 km north of Riga, Latvia, and 380 km east of Stockholm, Sweden. From the 13th century until the first half of the 20th century, Tallinn was known in most of the world by variants of its other historical name Reval.