Erfurt is the capital city of Thuringia and the main city nearest to the geographical centre of modern Germany, located south-west of Leipzig, north of Nuremberg and south east of Hanover. Together with neighboring cities Weimar and Jena it forms the central metropolitan area of Thuringia with approximately 200,000 inhabitants. Notable institutions in Erfurt are the Federal Labour Court of Germany, the University of Erfurt and the Fachhochschule Erfurt as well as the Roman Catholic Diocese of Erfurt with Erfurt Cathedral as one of the main sights. Further famous buildings are the Krämerbrücke, a bridge completely covered with dwellings, and Erfurt Synagogue which was established in the 11th century and is the oldest standing synagogue in Europe. Furthermore, the medieval city centre consists of old timber-framed houses and about 25 Gothic churches.Erfurt was first mentioned in 742, as Saint Boniface founded the diocese. Although the town did not belong to one of the Thuringian states politically, it quickly became the economic centre of the region. Until the Napoleonic era it was part of the Electorate of Mainz and afterwards it belonged to Prussia until 1945. The university was founded in 1392, closed in 1816 and reestablished after German reunification in 1994. It is one of the oldest universities in Germany. Martin Luther was the most famous student of the institution. Other famous Erfurtians are the medieval theologian Meister Eckhart, the Baroque composer Johann Pachelbel, the sociologist Max Weber and Gunda Niemann-Stirnemann, the most successful speed skater of all time.