The M-Bahn or Magnetbahn was an elevated Maglev train line operating in Berlin, Germany, experimentally from 1984 and in passenger operation from 1989 to 1991. The line was 1.6 kilometres (1 mi) in length, and featured three stations, two of which were newly constructed. Presumed to be the future of rail transit in Berlin, the line was built to fill a gap in the West Berlin public transport network created by the construction of the Berlin Wall. It was rendered redundant by the reunification of Berlin and was closed to enable reconstruction of the U2 line. It was Europe's only operational maglev line to this date.

Maglev is a system of rail transport whose rolling stock is levitated by electromagnets rather than rolled on wheels, eliminating rolling resistance.