Rockopolis

Rockopolis - This location is not a major landmark nor a random location and will not appear on your map. It is located due west of Smith Casey's Garage, due north of Girdershade and South East of the Yao Guai Tunnels. The entrance is a boulder that can be interacted with like any other door or entrance. Facing the boulder, there is one dead tree on the right, two on the left. And as the attached pictures show, there is a string of flags above the boulder. It should also be noted that the entrance is very close to the center of that particular square on the map.

History
According to files on Herbert Dashwood's computer and the accounts of The Adventures of Herbert "Daring" Dashwood on Galaxy News Radio, Rockopolis was once a hidden underground village. The inhabitants would only allow outsiders in if they presented with a secret knock. The mayor or king of Rockopolis at the time was King Crag. Herbert lead Penelope Chase, a slaver leader, to Rockopolis. According to Herbert Dashwood's computer, the incident lead to the enslavement of the city's population and the destruction of the city itself.

Adversaries
There is no one living inside. There is a random encounter right outside the entrance.

Radroaches outside at the entrance, a bunch of robots guarding the area. Protectrons, Robobrains, Sentry Bots, etc. as well as some Radscorpions and Giant Radscorpions.

One random event is one deathclaw beating the crap out of four raiders. For some reason, one was naked. There's also the small chance you encounter a group of four people (two ghouls and two Wastelanders right about to fight each other for water.

Another random event involves a man named Mel. Mel will attempt to rob you of your caps, but it's obvious he's never done this before. Having a high perception enables a speech option in which the PC notices that the gun isn't loaded. Mel can be scared off or killed, and in either choice he'll attempt to flee.