According to the Colorado Department of Public Health & Environment, six abandoned Cold War-era missile silos are hidden beneath the crust of the Centennial State: four are located in Aurora, one in Deer Trail, and another one in Elizabeth. They were designed for the Titan 1, one of the first intercontinental ballistic missiles that was created by the United States. At 98-feet long, this missile was designed to deliver nuclear warheads to a target.

Decommissioned in 1965, the silos were acquired by a variety of public and private owners and, for the most part, abandoned. Since the decommissioning, equipment has been removed, leaving expansive networks of vacant tunnels from a bygone era.

The site that tends to get the most attention is the missile silo near the town of Deer Trail, Colorado, a roughly 45 minute drive from Denver. Though the most accessible entrance to the complex is covered by a gate that’s since been welded shut, unknown urban explorers have illegally cut through the gate, gaining access.

Here’s a look at the abandoned complex during a guided tour with 9News out of Denver:

Inside the complex are long passageways linking enormous rooms, many of which are covered in rust and graffiti. According to reports of those that have been inside, a strong industrial scent hangs in the air. With no functioning electricity, the inside of the silo is pitch black. Many of the metal walkways have been partially or fully removed, posing huge risks for anyone the now takes the trip inside.

Aside from risking bodily injury by entering the Deer Trail-area missile silo, explorers also risk serious legal consequences. This silo is located on private property and entering it means trespassing. According to reports from many that have tried to enter illegally, the landowner and local law enforcement monitor the situation carefully and charge those that are caught.

According to the current owner of the Deer Trail silo, rancher Jerry Linnebur, he hates it when people try to enter his silo due to how dangerous exploring it can be. As of 2016, he had plans to close the entrance for good, following the arrest of more than 30 people.

While it may be tempting to check out this destination for yourself, don’t do it under any circumstance. It’s dangerous and illegal! Instead, watch the video above. It’s not worth potential injury or a criminal record.

Editor’s Note: This piece was originally published in 2017.

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