Donnie Darko was filmed in Los Angeles in the United States of America.
Locations
Vetter Mountain Trail
Forest Service Rd 3N16, Los Angeles, California 93550, United States
Scene where Donnie wakes up, not knowing what has happened.
Scene was shot Vetter Mountain Trail is a moderately trafficked loop trail. It is 6.4 kilometer long and located near Mount Wilson. Because of wild fires the trail is closed from October 2020 until April 2022. www.thennowmovielocations.com had some nice background info and comparatative photos about the exact location.