Full Basement map and walkthrough in Blue Prince

The Basement is a room in Blue Prince that you’ll need to access in order to reach Room 46. There’s a lot going on down there, and there are several ways to reach it.

Our Blue Prince guide will show you how to reach the Basement, give you the map of the Basement and Underground, and explain what to do down there.

How to get the Basement Key in Blue Prince

To get into the Basement, you’ll need to find the Basement Key. Happily, there’s a short answer to how to get the Basement Key: reach the Antechamber.

Reaching the Antechamber is a much longer process, though. You’ll need to find (at least) one of the three levers that open the Antechamber doors and then draft a path to that door.

Once you do that, you’ll pick up the Basement Key. The Basement key is your main way into the Basement. Even if you (eventually) find other paths in, you’ll still the Basement Key at least once.

How to use the Basement Key in Blue Prince

The easiest (well, relatively) way to get to the Basement is through the Foundation. You’ll need to draft it, move the lift down into position by revealing a hidden crank on the back side of the wall, and then take the elevator down where you will find a Basement door. To get that open, you’ll need the Basement Key (see above).

As you explore, you’ll find other ways into the basement like through the Cliffside Exit (if you have a Power Hammer), the Fountain (after you drain it), or the Tomb (in a roundabout way), but the Foundation is the most straightforward.

Full Basement and Underground map in Blue Prince

The Basement is part of a larger Underground complex in Blue Prince. You can find a complete map in the Reservoir’s rotating gear room, or see it below:

There are nine locations labeled on the map:

• Foundation elevator. This is the elevator in the Foundation that will bring you to the main Basement Door.
• Concealed Entrance. This is a hidden door that you open by solving the pallet jack puzzle in the Basement.
• Cliffside Exit. Outside of the house, go past the Fountain and down the stairs to where the blue braziers are. To the right, there’s a boarded up tunnel. If you have a Power Hammer (Sledgehammer + Battery Pack + Broken Lever in the Workshop), you can smash your way through. This opens a new path into the Basement.
• Mine Cart. The Mine Cart is just an obstacle that you can’t move from the Reservoir side. You’ll find a note about it in the Gemstone Cavern. To move it out of the way, you’ll need to solve the puzzle in the Tomb
• Fountain Entrance. With a bit of work, you can drain the Fountain in front of the house via the Pump Room. Doing so will reveal a new set of stairs and a new Basement door (that you’ll need the Basement Key for).
• Tomb Entrance. The Tomb is an Outer Room that you can draft once you unlock the West Gate Path. Inside, you’ll need to interact with the statues in a specific order to open a path to both the Mine Cart and the Reservoir.
• Torch Chamber. The Torch Chamber is an odd room that both relates to the larger Sigil puzzle and has torches you can light if you have the means (like with a Burning Glass made with a Magnifying Glass and a Metal Detector in the Workshop).
• Rotating Gear. This is your last puzzle to solve before reaching Room 46.
• To North Lever (and Room 46).

Basement walkthrough in Blue Prince

Since the Basement is part of the larger Underground, there’s a lot going on down there. There are also multiple goals you can achieve.

The most obvious is reaching Room 46. For that, you’ll have to:

1. Solve the Tomb puzzle by drafting the Tomb in the Outer Room and visiting the statues in order, and then move the Mine Cart out of the way (for later)
2. Solve the Basement’s pallet jack puzzle and open a path across the tops of the boxes to reach the Concealed Entrance
3. With the Mine Cart out of the way, you can solve the Rotating Gear puzzle to…
4. Reach Room 46.

While you’re down there, though, you can also:

• Drain the Reservoir via the Pump Room to get at some chests at the bottom.
• Explore the Torch Chamber and its Sigil puzzle.

One final note: The elevator you unlock by lighting the four braziers isn’t connected to the Underground or the Basement. That’s its own area, the Precipice, with its own puzzle — the chess puzzle.

For more Blue Prince guides, check out our full walkthrough on how to reach Room 46 or see our list of all safe codes.