The Washington Metropolitan Area Transit Authority is one of hundreds of transit agencies around the world that offer their data streams to the public using General Transit Feed Specification, a platform developed a few years ago by Google. The GTFS platform keeps track of train lines, bus routes, schedules and frequency of stops.

A YouTube user named STLTransit examined Metro’s data feed and created a time-lapse video that shows every Metro train and bus, along with Circulator buses, in a 24-hour period. The map is blacked out, save for a faint blue outline of the Potomac River, but as the day progresses, the shape of the District of Columbia starts to emerge from the flurry of dots traversing the screen. Metro and Circulator buses are represented by white blips, while Metrorail trips appear as color-corresponding dots. The video shows a 24-hour weekday beginning at 4 a.m.

And, oh, yeah, the music is suitably trippy. STLTransit also made videos for transit networks in dozens of other cities in the United States and Europe.