where is the berg metro station located?
It is located between Ullevål stadion and Tåsen stations
Berg metro station
 Located between Ullevål stadion and Tåsen stations, it is the first station after the Ring Line leaves the Sognsvann Line. 
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Berg metro station [SEP] Introduction
Berg is a station on the Sognsvann Line (line 6) of the Oslo Metro in Norway. Located between Ullevål stadion and Tåsen stations, it is the first station after the Ring Line leaves the Sognsvann Line. The station is located from Stortinget station. Berg is amongst the original stations on the line, and was opened on 10 October 1934. It was upgraded and rebuilt in the 1990s, when the Sognsvann Line was upgraded from light rail to rapid transit standard. Three accidents have taken place at Berg station, the latest in 2008. The area around the station is mainly residential.