In both games, this is a vertical shaft composed of green/blue bubble-like material, with multiple levels accessible by laying Bombs in or shooting through parts of the floor. It is located on the western side of Norfair and connects to multiple rooms.
In Metroid, it is a two-part, sparsely populated shaft with three total levels. The topmost level leads to the Screw Attack. The second and third levels are virtually identical, containing a ledge of bubbles and a midair platform beside it. These are used to get to the ceiling, where Samus can shoot her way up to climb the room. It is best to visit this shaft once the Varia Suit has been obtained. The second part of the room is accessed from an even lower hall in Norfair. While Samus cannot climb through the ceiling, she can drop through the floor into a shaft resembling others in Norfair to access a room with Missile Tanks.
In Victory Techniques for Metroid, Samus comes to this room on page 97. The guide includes a tutorial on getting through the ceiling to the Screw Attack's door.
In Zero Mission, the shaft features more solid obstructions between floors. Only about three levels are initially accessible, while two more can be reached via other exits. The topmost level, which leads to the Screw Attack, can be reached by firing at Missile Blocks directly into the ceiling on the left side, allowing Samus to get the Screw Attack before she enters Ridley's Lair. After the Screw Attack is obtained, it is possible to shred through the other half of the floor, which is comprised of Screw Attack Blocks. If Samus defeats Ridley first and returns to Norfair, a Morph Ball launcher in the room directly below this shaft can be used to launch Samus through the entire shaft up to the Screw Attack corridor's door. The floor in the lower part of the shaft, as in Metroid, can be Bombed to unearth more of the room and reveal a path to the same two Missile Tanks.
- "Brutal path" (Metroid, via Blue Door)
- Save Room 3 (Zero Mission, via Blue Door)
- "Screw Attack corridor" (via Blue Door)
- "Three rock corridor" (via Blue Door)
- "Twin hill corridor" (via Blue Door)
- "Precarious path" (via Green Hatch)
- Hopping-Mad Corridor (via Blue Door)
- "Vine-infested passage" (via Blue Door)
- "Dual tank chamber" (via Blue Door)
- "Norfair transporter" (Zero Mission, via one-way Morph Ball launcher)
- 019 POWER-UP BREAK-THROUGH (pg. 133)
- "By using Bombs in the room where you collected the High Jump Boots, you can uncover a path to one of the corridors that runs through the middle of Norfair. Run left through the corridor and stop at the room that has green bubble-bricks on the walls and ceiling. Blast through the ceiling from the upper-right ledge and continue on to the Screw Attack ledge."
- 020 LAVA DIP (pg. 133)
- "After you collect the Screw Attack, return to the green room and bomb through the floor to a lower corridor."
- 135 DROP AND FIGHT (pg. 58)
- "If you choose the low road, create a hole in the area between two blue hatches, drop and run to the left."
- 139 missile tank (pg. 59)
- "When you reach the one-screen-wide room, blast through the floor, drop and move to the right, through a hot-air corridor."
- 183 EXPRESS ROUTE THROUGH NORFAIR (pg. 69)
- "Roll into the launcher and set a bomb. On detonation, you'll take off for Norfair's upper-left section."
- 187 DOWN AND TO THE RIGHT (pg. 70)
- "Use the Screw Attack to cut through the floor and burrow down to the save room's level, then blast your way down another level to the green hatch. Move to the right through the hatch."