This room is a corridor which serves to connect several rooms of the Command Sector. The corridor is fairly long, and splits into 3 three routes at the east end. The west of the room features one door linking to Security Air Lock. The room can be accessed via a caged tunnel that leads up the right wall of the room. However, this can not be entered from this room due to the tunnel being vertical.
At the right and left of the east end of the room are two shields. The left one is a metal door that can be deactivated by the use of a Pirate X-Ray Pad next to it. The X-Ray Visor is required to successfully use it, though. Behind this hatch is a small slope that leads to an elevator, which can rise up to a higher level of Defense Access. A Blue Door here will link to a balcony area of Command Station.
The right shield in the room is powered by a nearby Grapple Voltage Terminal. The shield cannot be deactivated from this side, and the Grapple Voltage must be used for its removal. Both shields will remain permanently offline when deactivated. The other side of this shield leads down a short slope to a circular and tall part of Defense Access. This area links one-way from Skyway Access, through a Kinetic Orb transportation device that launches spheres at great speeds through the tunnels. This exit tunnel is located at the bottom of the shaft, and is slightly raised from the floor. The tunnel is caged over, and it is impossible to enter from Defense Access due to a vertical curve at the exit point. Also in this shaft area, there is a Spider Ball Track that ascends and curves around the room. The shaft is segmented in places by spinning gears that span around the perimeter of the room at various levels. At the top of the room here is a ledge, linked to by the Spider Ball Track that has a Blue Door. This door leads to a Transit Station linking to the Mining Site.
Finally, the Green Door at the east end of the corridor can be covered by a Phazite-plated wall, which will deploy when an unauthorised presence is detected in the vicinity. This mechanism is a failsafe to stop intruders reaching the important defense system generator located in the connecting room, Command Station. This shield can be raised if the user targets the vulnerable gears inside the Phazite with a high-frequency Beam, used in conjunction with an X-Ray vision system.
- 2 Assault Pirate Troopers (only after Samus uses the elevator to reach the balcony of Command Station and returns)
- Security Air Lock (Blue Door)
- Command Station (via one Green Door and one Blue Door)
- Command Vault (via Morph Ball tunnels)
- Skyway Access (via one way long-distance Morph Ball tunnel)
- Transit Station 4-A (via Blue Door)
- Security gate
- "Security gate engaged. Phazite plating can only be penetrated by high-frequency Beam weapons."
- Grapple Voltage Terminal
- "Terminal controls the nearby energy shield. Drain the device of power to remove the shield."
- Grapple Voltage Terminal (drained)
- "Terminal is drained of power. Nearby energy shield is offline. Unit cannot be used again."
- Pirate X-Ray Pad
- "Control terminal operates nearby door. Interact with the terminal to open the door."
- Pirate X-Ray Pad (used)
- "Control terminal has opened nearby door. Control terminal can no longer be used."