In all three games, this room serves as the entrance to Tourian. It is a shaft of varying length - it is longest in Metroid, and roughly the same size in Zero Mission and Super Metroid. In the former two games, it is accessed via elevator from Brinstar, while in Super Metroid the new Tourian is accessed from Crateria.
The shaft is populated with six Metroid larvae, which begin to target Samus when they spot her. Visually, the room is similar to the escape shaft at the other end of Tourian, as they share the same metal constructed walls, and midair blue platforms of varying width. At the bottom of the shaft is a Yellow Door requiring ten Missiles, which leads into the rest of Tourian. This is the only such door in the game.
Zero Mission, the remake of Metroid, divides the room into two halves and makes it shorter. It also contains fewer Metroids than the original game, placing one of them into a new room. The first part of the shaft features the elevator platform, a single square platform on the left wall, and a Blue Door to the right, with a floor separating the rest of the shaft.
After Samus progresses through the door and a couple of rooms, she returns here through the lower half of the shaft. This half features elongated platforms, now metallic gray instead of blue, and they are arranged almost as if they are a staircase. Two or four Metroids (depending on the difficulty mode) are found here, as is a Zebesian's brittle husk at the bottom of the shaft. This room curiously remains intact after the destruction of Tourian, despite the base's explosion covering a rather large radius (as seen on the surface of Zebes).
Super Metroid features a new entrance shaft for Tourian, while the original shaft (as well as most of the original Tourian) is no longer accessible. This shaft is much shorter than the previous incarnation and contains no Metroids. It has two ledges on either side, followed by a single platform over a pool of scalding-hot lava. A door on the right leads into a Save Station. To continue through Tourian, Samus must proceed through the left door.
- "Transport to Tourian" (via Elevator)
- "Tourian lava passage" (via Yellow Door in Metroid, Blue Door in Zero Mission)
- Mysterious Statue Chamber (via Elevator)
- Tourian Save Station 1 (via Blue Door)
- "Metroid passage 1" (via Blue Door)
- 202 DROP AND POP (page 74)
- "After one meeting with a Metroid, you'll come across two more in a short shaft. Descend slowly, wait for the Metroids to appear and take them on one at a time. Freeze them and blast them."