Caverns

Caverns is a single-level PWAD for Doom that was released in 1994. It was designed by Knightmare (Doug Dziedzic).

Secrets

 * 1) From the south-western room near the exit, take the staircase that leads north-east. The path continues to a door to a room with several items and a candelabra in the north-west. The walls to the north and south of this candelabra are secret doors both leading to a room with a demon, some ammo, a medikit, an invulnerability (not on hard skill), and a radiation shielding suit. There is fake wall to the south-west leading to four stimpacks (multiplayer only) and a chainsaw. Both the room itself and the two doors count as separate secrets. (sector 124)
 * 2) See #1. (sector 125)
 * 3) See #1. (sector 126)
 * 4) One of the niches to the east en route to the door at the end of the path mentioned above is a secret door leading to an area with 0-3 cacodemons, a baron of Hell, two boxes of rockets, and a rocket launcher. (sector 120)
 * 5) The room south of the BFG9000 room has a secret door to the south-east (at the end of the lava trench) leading to a room with a demon, four lost souls (not on easy skill), a plasma rifle, and a berserk. On multiplayer there are also three energy cells. (sector 11)
 * 6) In the BFG9000 room, head towards the north-west past the partial invisibility. There is a secret door to the north (in easy and medium skills there is a dead player marking it) leading to four stimpacks (not on hard skill), an invulnerability (not on hard skill), a berserk, and a door to a teleporter which takes you to the switch which raises the stairs to the exit. (sector 215)

Bugs
The switch which raises the stairs to the exit can be pressed through the fence, making a large part of the level redundant.

Current records
The records for the map at the Doom Speed Demo Archive are:

Player spawns
This level contains six spawn points:
 * 1) facing south-east. (thing 246)
 * 2) facing north-west. (thing 248)
 * 3) facing south. (thing 262)
 * 4) facing east. (thing 263)
 * 5) facing west. (thing 291)
 * 6) facing south. (thing 330)

Things
This level contains the following numbers of things per skill level: