Wikipedia
Frøen is a rapid transit station of the Oslo Metro's Holmenkollen Line and previously also the Sognsvann Line. It is situated Frøen neighborhood of the Oslo, Norway, borough of Vestre Aker. Located from Stortinget, the station is served by Line 1 of the metro every fifteen minutes. Travel time to Stortinget is six minutes. Diakonhjemmet Hospital falls within the station's catchment area.
The initial station opened on 31 May 1898. With the construction of the Sognsvann Line, Frøen became both a stop on it as well as the interchange between the two lines. It therefore received four separate platforms at three different elevations. It served trains on the Sognsvann Line from 10 October 1934 until 1992. Frøen received a slight upgrade in 2010. However, Ruter plans to close it down and replace it and Steinerud with a new station.