Tallinn and Helsinki: The twin cities

Helsinki in Finland and Tallinn in Estonia are often called twin cities because of their proximity, the trip across the Gulf of Finland little more than 80km in length, far less than the distance from either capital to the second-largest city in their respective countries. The journey between the two is a popular and well-used route: Helsinki has 650,000 inhabitants and Tallinn 450,000, but last year 6,150,000 passengers travelled between the cities.