Wikimedia Commons/Jeffrey Beall
The new overpass spans six highway lanes.
Colorado opened the I-25 Greenland Wildlife Overpass in December 2025, and it is now North America’s largest wildlife crossing by surface area.
The Colorado Department of Transportation announced the opening on December 22. The massive structure sits near Larkspur in Douglas County, between Castle Rock and Monument.
More than 100,000 vehicles travel this stretch of Interstate 25 every day, making it one of the busiest corridors in the state.
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Structure covers nearly one acre
The overpass measures 200 feet wide and 209 feet long, covering nearly one acre of space. That adds up to 41,800 square feet of crossing area for wildlife…