Berlin is in Germany. It lies at the heart of the North German Plain in the wide glacial valley of the Spree River, which runs through the center of the city. It is situated about 112 miles (180 km) south of the Baltic Sea, 118 miles (190 km) north of the Czech-German border, 110 miles (177 km) east of the former inner-German border, and 55 miles (89 km) west of Poland.