The Underground City Inside of Colorado’s 9,570-foot Cheyenne Mountain

Looming above Colorado Springs, Colorado, the 9,570′ Cheyenne Mountain often sparks curiosity from onlookers due to the number of blinking antennas found on the top of the peak. Perhaps what’s more interesting is what’s inside.

The mountain is home to a sprawling complex, Cheyenne Mountain Complex, that was built in the 60s. It spans approximately 5 acres of space, including more than a dozen three-story buildings. It’s been used for a number of things, including the operations of the North American Aerospace Defense Command (NORAD).

Perhaps even more intriguing is that the complex was built to withstand an electromagnetic pulse and a 30-megaton nuclear explosion as close as 1.2 miles away. To put that in perspective, the most powerful bomb ever detonated by the United States had a yield of 15 megatons.

Check out the video below, created by 9NEWS, for an inside look at this unique feature of Olympic City, USA.