Rock Creek Caverns

 is a large disconnected metro tunnel/cavern that is inhabited by Mirelurks, Mirelurk Hunters, or Mirelurk Kings depending on the character's level. The caverns consist of a single interior section.

Exterior
The entrance to Rock Creek Caverns is accessed through a sewer grate at the bottom of a crater that has exposed the sewer system, just to the west of the National Guard Depot. When coming from the direction of the National Guard Depot, there is a guaranteed encounter with two raiders and two Super Mutants most likely wielding big guns.

Rock Creek Caverns
This section is the only section in, but is a large section incorporating numerous tunnels and offshoots as well as brief areas of the metro system. 15 Mirelurks are scattered around the section. At point D on the local map image seen above, there is a bed that can be slept in along with a safe. At Point F there is a mercenary and wastelander corpse along with an "easy" safe and a few ammo boxes. Point G has a dead skeletal family and a few stimpaks along with some various loot. Point E just has some dead Brahmin and dead ants along with some egg clutches.

Notable loot

 * A Nuka-Cola Quantum can be found in a wooden crate at B on the local map image. To get to it, walk up the fallen stalactite at A, which rests at an angle against a wall in the first and largest chamber of Rock Creek Caverns. At its tip, jump up to where some mushrooms are located. Hugging the wall, walk on the skinny ledge around to B.

Appearances
appears in Fallout 3.

Trivia

 * Rock Creek Caverns got the name "Rock Creek" from the Rock Creek Pkwy in Washington DC. Rock Creek Pkwy is located near the Washington Monument in Washington DC.