Blue Prince Sanctum Key

Every Blue Prince Sanctum Key Location

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Published: April 13, 2025 11:09 AM

As you continue to hunt through the mansion of Blue Prince if you haven't been finding Red Letters chances are you've stumbled across a Sanctum Key. These 8 keys are tied to the locked doors in the Inner Sanctum, we'll show you how to get them all.

At this point you've likely already reached Room 46, but if you haven't that should be your first goal. After reaching Room 46 for the first time you can recomplete the task,and then explore the room. Inside is a document hinting of the locations of each of the Sanctum Keys, it reads as follows:

The first key found here on the furthest rank,
The second locked tight in the vault of a bank,
The third is high up, among all the clocks,
And the fourth down below, beneath all the docks.
The fifth key is held by a king on his throne,
The sixth in a station, left by one of your own,
The seventh is major if you draft it quite late,
And the last key is waiting, behind the last door of eight

For each of these keys we'll list hints to their locations before we supply you with the solutions and any additional hints so feel free to skip to the key you're after.

Note: Before we get started with this, Sanctum doors once opened will stay open, but if you get the key and can't make it to the inner sanctum then the key will return to its hiding place and you'll need to re-obtain it.

Sanctum Key Locations

The First Key

We won't go too much into the location of the key because if you've read the original riddle chances are you've also already picked up the Sanctum Key in this room

The Second Key

Hint #1 - This key is located in the Vault room

Hint #2 - It requires a special key to access it

Blue Prince Gallery Vault Sanctum Key

Some tips in order to make getting this a bit easier:

  • Draft the Trading Post Outer Room, collect a lot of items and the Vault (or the Coat Check) and trade a lot of items. There's a chance the vault key will appear.
  • Most placed a Major Key can appear the Vault Key can show up
  • The Vault can be spawned more reliably if you get the Dead End star sign in the Observatory
 
Vault Key Solution <Click To Expand>

    The Third Key

    Hint #1 - You'll need to get the Clock Tower from the Drafting Room

    Hint #2 - Inside the Clock Tower see if you can notice anything static or out of place compared to others

    Hint #3 - Wait until 1:30pm while inside the Clock Tower

    Hint #4 - Make sure you've paid attention to how to tell what memos are true, and which lie

    Hint #5 - Start using the clues that you know for certain are true to block off certainties, and then work within the confines of what you have left
    I.e Clock #5 must be 7pm and there must be 5 'on the hour' times

     
    Clock Tower Solution <Click To Expand>

    The Fourth Key

    Hint #1 - This key is not in the house

    Hint #2 - You'll need to drain the Reservoir fully to reach this

    Hint #3 - You can use the Reserve Tank in the Pump Room if you've powered it with the Boiler Room

    Hint #4 - The key is inside one of the boxes at the bottom of the Reservoir, incorrect boxes may have clues to the location of the key

     
    Reservoir Sanctum Key Location <Click To Expand>

    The Fifth Key

    Hint #1 - You'll need to reach the Throne Room

    Hint #2 - The Throne Room can be obtained after completing something in the Blackbridge Grotto

    Blue Prince Throne Room
     
    Fifth Sanctum Key Solution <Click To Expand>

    The Sixth Key

    Hint #1 - This key is not in the house

    Hint #2 - There is another clue for this key near where Red Letter #1 can be found

    Hint #3 - You'll need the pump room and the reservoir partially drained to access this key

    Hint #4 - Make sure the Boat is on the correct side of the Reservoir

     
    Safe House Sanctum Key Solution <Click To Expand>

    The Seventh Key

    Hint #1 - Major isn't just a reference to this being a Major Key

    Hint #2 - Late doesn't mean higher rank in the house

    Hint #3 - It's lovely hearing some music in the evening

     
    Seventh Sanctum Key Solution <Click To Expand>

    The Eighth Key

    Hint #1 - The room that this key spawns in needs to be obtained via the Drafting Room

    Hint #2 - Having the wrench could help making this task easier

    Hint #3 - If the room can't spawn a door the number of rooms you need is decreased

     
    Eighth Sanctum Key Solution <Click To Expand>

    Once you have all of the Sanctum Doors open then you can work on the Sigil puzzles inside.

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    More Info About This Game
    Learn More About Blue Prince
    Game Page Blue Prince
    Developer
    Dogubomb
    Publisher
    Raw Fury
    Release Date
    April 10, 2025 (Calendar)
    Genre
    Puzzle, Roguelike
    Purchase (Some links may be affiliated)