Lithuania, officially the Republic of Lithuania is a country in Northern Europe, the southernmost of the three Baltic states. Situated along the southeastern shore of the Baltic Sea, it shares borders with Latvia to the north, Belarus to the southeast, Poland, and the Russian exclave of Kaliningrad to the southwest. Across the Baltic Sea to the west lies Sweden and Denmark. Its population is 3.28 million. Its capital and largest city is Vilnius. Lithuania is a member of NATO, the Council of Europe, and the European Union. Lithuania became a full member of the Schengen Agreement on 21 December 2007. In 2009, Vilnius was the European Capital of Culture and Lithuania celebrated the millennium of its name.