Yao Guai Tunnels

The Yao Guai Tunnels are located due west of the Charnel House, and northwest of Smith Casey's Garage. The entrance is a chain-link fence door in a rocky outcrop. As the name suggests, the caves are inhabited by a large number of Yao Guai.

Notable Loot

 * There is a Pre-War Book, Sensor Module, and Toy Car on the picnic table just as you enter the Tunnels, and a random weapon behind a pile of sandbags next to the picnic table, in the cabinet. Custom weapon parts on shelf further down and if you stay left more parts in a dead end.
 * There is a bottle of Nuka-Cola Quantum on a table near a radio, on the way to get the Bobblehead - Sneak (see below).
 * Floating in the pool of water next to the bobblehead is a settler's corpse containing the Yao Guai Den Note about setting up camp in the tunnels.
 * In the southern section of the Yao Guai Tunnels there is a Grognak the Barbarian book along with a dead Raider on ledge directly in front of the one-way exit out of the Yao Guai Den. You cannot reach this from the tunnel floor, you must travel through the den and exit by the ledge.

Bobblehead Location
To find the Bobblehead - Sneak, you will enter facing east, continue east until you have the choice go north or south - go north and follow this path around a pillar, now going south, past 3 ammo boxes by a table, to the den. Once inside the Den, walk straight ahead to the central pillar (not one in small room with all the skeletons. Keep going into large open area), and then head to the left. Immediately look for the natural stone ramp that leads along the eastern edge of the cavern, overlooking a crescent-shaped pool of water. At the base of the ramp (Directly behind pillar with dead wastelander in the hole up high) is a Metal Box with the bobblehead standing on top of it.

Enclave Outpost
After the quest "Waters of Life" you will find an Enclave camp directly east of this position. They usually are all dead, with clear signs of a struggle all around. They may have been studying the Yao Guai for ways to control them similar to the Enclave Deathclaws, or may have simply not known about the Yao Guai den when they set up the outpost. Also, a Vertibird has been known to land nearby (or other mini-encounter involving Enclave soldier(s) happen). The Enclave camp may not be around until you go into the caves and back out again (confirmed PC and 360).

Bugs
Targeting the first Yao Guai that runs across the screen at the start of the cave (it has no AI and disappears after it is first seen) in V.A.T.S. can cause the game to freeze.