Bohemia, a historic region of central Europe that in the Middle Ages was a powerful kingdom. Today it forms the western part of the Czech Republic, covering an area of about 20,000 square miles (52,000 km2). On the east, it adjoins the region of Moravia; on the northeast, Poland; on the west, Germany; and on the south, Austria. Prague (Praha), capital of the former Bohemian kingdom and of the Czech Republic, is just north of the center of Bohemia, on the Vltava (Moldau) River.