In the Swedish city of Gothenburg the tram network has a curious section of track – a diamond crossing that swaps the left and right tracks around.
Sweden switched from driving on the left-hand side of the road to the right on 3 September 1967, the day being Dagen H or “Högertrafikomläggningen” (“The right-hand traffic diversion”).
Tram operator Göteborgs Spårvägar started planning for the change from 1964, with 27 trams, 24 trailers and a bus converted for right-hand traffic, and 53 new motor-buses for right-hand traffic purchased. In 1965, 30 new right-hand trams were added.
Another planned project of the 1960s was the conversion of the tramways to an underground rapid transit system, so new tram extensions were built to ‘premetro‘ standards.
Line 8 from Frölunda to Angered is one example, with tramway passing through city streets using traditional right-hand running.
But to save on construction costs in the underground section, it was decided to build an island platform at Hammarkullen, which required the single-directional trams to use left-hand running through the tunnels.
Which required trams to switch from left- to right-hand running partway along the route – at the Hjällbo stop.
The crossover is at grade, so only one tram can occupy it at a time.