The Free State of Thuringia is a federal state of Germany, located in the central part of the country. It has an area of 16,171 square kilometres (6,244 sq mi) and 2.29 million inhabitants, making it the sixth smallest by area and the fifth smallest by population of Germany's sixteen states. Most of Thuringia is within the watershed of the Saale, a left tributary of the Elbe. Its capital is Erfurt. Thuringia has been known by the nickname of "the green heart of Germany" ) from the late 19th century, due to the dense forest covering the land. Thuringia is known in Germany for nature and winter sports. It is home to the Rennsteig, Germany's most famous hiking trail, and the winter resort of Oberhof. Germany has won more Winter Olympics gold medals than any other country in the last 20 years, and half of Germany's gold medals have been won by Thuringian athletes. Johann Sebastian Bach spent the first part of his life (1685-1717) and important further stages of his career in Thuringia. In the classical period,Goethe and Schiller lived at Weimar. Both worked also in the famous University of Jena nearby, which now hosts the most important centre of science in Thuringia. Other Universities of this federal state are the TU Ilmenau, the University of Erfurt, and the Bauhaus University of Weimar.