Sigur Rós have revealed the details on “Route One,” the livestream event they’ve been teasing throughout the day. According to a press release, it’s a 24-hour “Slow TV” broadcast on Iceland’s National Television channel RÚV 2 and YouTube, set to a constantly evolving soundtrack based around elements of new song ‘Óveður’,” the one they debuted at Primavera Sound.

Beginning at tonight’s Summer Solstice and continuing through the longest day of the year, the broadcast will trace a 1,332 kilometer trip counterclockwise around Iceland’s coastal ring road, passing national landmarks including Vatnajökull (Europe’s largest ice-sheet), Jökulsárlón (a glacial lagoon), the East Fjords, and “the desolate black sands of Möðrudalur.” Explains frontman Jónsi Birgisson, “In a day and age of instant gratification and everything moving so fast, we wanted to do the exact opposite. Slow TV is counter-active to the world we live in, in that it happens in real time and real slow.”

The press release explains how “Óveður” factors into this:

The soundtrack to the journey is being created moment-by-moment via generative music software. The individual musical elements of unreleased song and current Sigur Rós festival set opener, “Óveður,” are seeded through the evolving music app Bronze to create a unique ephemeral sonic experience. Headphones, external speakers and full-screen viewing are recommended.

UPDATE: Sigur Rós have shared a 5-minute timelapse of the 24 hour livestream. The studio version of “Óveður” soundtracks the newly condensed clip. Watch below: