Ostrava is a city in the north-east of the Czech Republic, and the capital of the Moravian-Silesian Region. It has about 285,000 inhabitants. It lies 15 km from the border with Poland, at the confluences of four rivers: Oder, Opava, Ostravice and Lučina. Ostrava is the third largest city in the Czech Republic in terms of both population and area, the second largest city in the region of Moravia, and the largest city in the historical land of Czech Silesia. It straddles the border of the two historic provinces of Moravia and Silesia. The wider conurbation – which also includes the towns of Bohumín, Havířov, Karviná, Orlová, Petřvald and Rychvald – is home to about 500,000 people, making it the largest urban area in the Czech Republic apart from the capital, Prague.
Ostrava grew in importance due to its position at the heart of a major coalfield, becoming an important industrial engine of the Austrian empire. During the 20th century it was known as the "steel heart" of Czechoslovakia thanks to its status as a coal-mining and metallurgical centre, but since the Velvet Revolution it has undergone radical and far-reaching changes to its economic base.