'''Tallinn''' (; ) is the most populous, primate, and capital 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 444,532 (as of 2021) and administratively lies in the Harju ''maakond'' (county). Tallinn is the main financial, industrial and cultural centre of Estonia. It is located  northwest of the country's second largest city Tartu, however only  south of Helsinki, Finland,  west of Saint Petersburg, Russia,  north of Riga, Latvia, and  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'''.