Sentinel site

Sentinel Site Prescott, simply called sentinel site in the game, is a location in the Glowing Sea region of the Commonwealth in 2287.
The facility is one of the few places in the Glowing Sea hardened against radiation, so the player character can safely remove whatever gear they are using to prevent radiation damage while inside.
Background A pyramid structure surrounded by irradiated sludge, Sentinel Site Prescott was officially a nuclear munitions disposal facility. However, in reality, it was a missile silo that stockpiled Mark 28 nuclear warheads for the U.S. military, and performed experiments focused on combining them with existing ballistic missiles.
With a seemingly inexhaustible stock of these warheads, they performed at least 23 test launches, the final one performed on the eve of the Great War. The launch failed to register with the system, locking the hapless staff inside and dooming them to death of hunger and thirst. Many were turned into feral ghouls, sealed beneath the ground. Captain Dunleavy of the 132nd Engineering Corps operating the site recorded the final moments of the crew before the first MIRVs hit the Commonwealth and he realized that the Great War happened.
By 2281, the site was penetrated by the Children of Atom, who were able to activate the launch sequence before being massacred by the feral ghoul inhabitants. Although no missile was present on the launch pad, all internal blast doors in the facility were closed and locked, requiring the Sole Survivor to deactivate the sequence in order to gain full access to the facility. The Brotherhood of Steel followed later, seeking to provide Liberty Prime with a new supply of nuclear weapons, straight from Prescott's silos.