Poland, officially the Republic of Poland, is a country located in Central Europe, forming a crucial crossroads between Western and Eastern Europe. Its geography is defined by a varied landscape, extending from the Baltic Sea in the north to the Carpathian and Sudetes mountain ranges in the south. The nation's history is marked by periods of great power and decline, from the Polish-Lithuanian Commonwealth to its modern status as a key member of the European Union. The population, estimated at over 37.9 million people, resides in a country with an area of 312,679 km². The capital and largest city is Warsaw, which serves as the primary economic and cultural hub.