Jem Finer’s Longplayer started playing at the start of the millennium and will last until its end.

Joseph Beuys planted the first tree of 7000 Eichen - Stadtverwaldung statt Stadtverwaltung (a.k.a. 7000 Oaks or 7000 Trees) in front of the Fridericianum.

Xirabreşk (a.k.a. Göbekli Tepe) may be the oldest human monument we’ve found. It was built almost 12 millennia ago, likely as a temple.

John Cage’s As Slow As Possible (ASAP) has been playing in the church of St. Burchardi since 2001.

De Letters van Utrecht (the Letters of Utrecht) begins in front of Oudegracht 279.