Cheyenne Mountain Space Force Station

Cheyenne Mountain Space Force Station (CMSFS) is located in Cheyenne Mountain on the Front Range of the Rocky Mountains in unincorporated El Paso County, Colorado, next to Colorado Springs, The Cheyenne Mountain Complex, an underground facility within Cheyenne Mountain SFS, was first built for the North American Aerospace Defense Command (NORAD) Combat Operations Center, though NORAD moved day-to-day operations to its headquarters on Peterson AFB in 2006. However, day-to-day operations were moved back in 2011 after a major overhaul and renovation.

Source: Wikipedia — Cheyenne Mountain Space Force Station (CC BY-SA 4.0)