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. History Frøen was a station on the original Holmenkollen Line opened on 31 May 1898. At the time the line followed the road Slemdalsveien, in a curve past Frøen. The station took its name from Store Frøen and Lille Frøen, two farms in the area. The tram line allowed for sufficient public transport that housing development started in the area. Construction of the Sognsvann Line started in 1933. The branch between the two lines was set to be at Frøen. To make room, the pond of Frøensdammene were dammed up and the tracks placed on the former pondbed. An interchange was established, so there were four platforms, with separate platforms serving each of the two lines. During the Second World War a bomb was blown on the Sognsvann Line at Frøen. No-one was injured and only a few meters of track were damaged. They were quickly rebuilt. During the 1980s the platforms received a standard, blue waiting shed designed by Odd Thorsen. The Sognsvanns Line was rebuilt to metro standard in 1993. At this time it was found that it would not be feasible to extend the platforms for that line to the nominal length of . It was therefore decided that the Sognsvann Line would no longer have a stop at Frøen. This was met with protests from some, as the Sognsvann Line would no longer have a suitable stop to serve Diakonhjemmet. From 1993 until the Holmenkollen Line was closed for renovations in 2009, Frøen was the site where the trains switched between third-rail and overhead wire power supply.