The Grorud Line is a 13.0-kilometer-long line on the Oslo Metro between Tøyen and Vestli in Oslo, Norway. Built as a mix of underground, at ground level and as an elevated line, it runs through the no

The Common Tunnel, sometimes called the Common Line, is a 7.3-kilometer long tunnel of the Oslo Metro which runs through the city center of Oslo, Norway. The name derives from the fact that all five l