Sound Transit has published an engaging video to its YouTube channel, showing the underground path of its next northward push from the University of Washington station to the U-District station.

The 4,874-foot extension is part of a planned line that will eventually link Northgate to the UW, downtown and Sea-Tac Airport.

The video shows the path of the twin tunnels -- in Husky purple! -- overlaid on a drone's overhead view, with the tunnels right underneath the Hub, the Quad and Kane Hall.

Once completed, riders will be able to travel from the U-District station at Brooklyn Avenue and Northeast 45th Street to downtown Seattle (Westlake station) in eight minutes, and to the airport in 41 minutes. Going in the other direction, travel time to Northgate will be just five minutes.

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But! You'll have to wait until 2021 to make the trip, even though the twin tunnels were dug in 2016. Patience, please!