The Helsinki Metro, opened in 1982, is the only metro system in Finland, albeit the Helsinki commuter rail trains operate at metro-like frequencies. In 2006, the construction of the long debated extension of the metro into Western Helsinki and Espoo was approved. The extension finally opened after delays in November 2017. An eastern extension into the planned new district of Östersundom and neighboring Sipoo has also been seriously debated. Helsinki's metro system consists of 25 stations, with 14 of them underground.