Warsaw, known also by other names, is the capital of Poland and its largest city. It is located on the Vistula River roughly 370 kilometers (230 mi) from both the Baltic Sea coast and the Carpathian Mountains. Its population as of 2006 was estimated at 1,700,536, with a metropolitan area of approximately 2,900,000 to 3,000,000 people. The city area is 516.9 square kilometers (199.6 sq mi), with an agglomeration of 6,100.43 square kilometers (2,355.4 sq mi) (Warsaw Metro Area - Obszar Metropolitalny Warszawy). Warsaw is the 8th biggest city in the European Union.
Warsaw gave its name to the Warsaw Pact, Warsaw Convention and the Treaty of Warsaw.
Warsaw straddles the Vistula River. It is located in the heartland of the Masovian Plain, and its average altitude is 100 metres (330 ft) above sea level, although there are some hills (mostly artificial) located within the confines of the city.