A few years ago, a group of scientists found something remarkable deep beneath Stockholm, on the granite walls of the deepest metro station in the city — Kungsträdgården. The station bears the same name as the park it is located beneath, one of the oldest parks in the centre of Stockholm, facing the Royal Palace. In this subterranean world, the researchers found an unexplored ecosystem that was developing in the underground passageways: plants and creatures that didn’t exist anywhere else in the city, such as whorled tufa moss, last seen in Stockholm growing in a greenhouse in the 1930s. They also found dwarfweaver spiders, more usually found in catacombs in Southern Europe. No one was able to explain how these exotic non-native species had found their way into Kungsträdgården metro station.
Perhaps it was appropriate that the mystery arose there because in many ways Kungsträdgården is a remarkable metro station. From the moment you step onto the escalator and head down towards the platforms, you are struck by a very specific smell. Not the dust or hot metal of other stations, but soil, like an old cellar. The rock walls are bare, untreated — the only station to be left that way in the whole of the Stockholm metro network. Between 1978 and 1986 artist Ulrik Samuelson transformed Kungsträdgården metro station into one of the most spectacular tube stops in the world — an immersive, underground installation of romantic decay.