Estonia is one of three Baltic countries, which has been dominated by foreign powers through much of its history. In fact, in 1940 it was incorporated into the U.S.S.R. as one of its republics. Estonia then remained a Soviet republic until 1991 when it received its independence. This country is home to 1.3 million people and 22% of them are Russians.
The city of Tallinn is pretty small and quite walkable, and therefore you can see most of Tallinn’s top sights in a day really, but I would recommend two days at maximum. Tallinn is the capital of Estonia whose Old Town subdistrict is actually a designated UNESCO World Heritage Site.