Douglas County - Elk, pronghorn, mule deer, black bears, mountain lions and a variety of other species are now able to cross the I-25 Greenland wildlife overpass near Larkspur, which is North America’s largest wildlife overpass. Earlier this month, the Colorado Department completed construction of the structure, including covering the overpass surface with dirt and vegetation. The project was completed in less than a year, ahead of schedule, and on budget.