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The Skybridge does not carry automotive vehicles, as the neighbouring Pattullo Bridge does, but has two tracks enabling the TransLinkSkyTrain to pass either way on the bridge on its journey between King George Station in Surrey and Waterfront Station in downtown Vancouver. An additional third set of rails in the middle is used by maintenance crews to truck equipment back and forth on the bridge (not connected to the SkyTrain tracks). The bridge has two 123 m (404 ft) tall towers and carries trains 45 m (150 ft) above the Fraser river and valley. The main span is 340 metres (1,115 ft) and the total length is 616 m (2020 ft), making it the longest transit-only bridge in the world.