Erlangen (East Franconian: Erlang) is a Middle Franconian city in Bavaria, Germany. It is located at the confluence of the river Regnitz and its large tributary, the Untere Schwabach. Erlangen has more than 100,000 inhabitants.
Erlangen is today dominated by the University of Erlangen-Nuremberg and the numerous branch offices of Siemens AG, as well as a large research Institute of the Fraunhofer Society and the Max Planck Institute for the Science of Light. An event that left its mark on the city was the settlement of Huguenots after the withdrawal of the Edict of Nantes in 1685.
Felix Klein's Erlangen program, considering the future of research in mathematics, is so called because Klein was then at the University of Erlangen-Nuremberg