Maps are taken directly from the game, resized to twice their original size, and annotated with the contents of chests before being uploaded here.
The map annotation process is currently a work in progress. For raw and unpolished annotated maps, you can see eye_heart's raw map images in the gallery of his notes page, or you can look at SoulHX's Labyrinth.os notes document for a complete collection of un-annotated maps.
Items found in chests are listed separately from the images as text, so you can use ctrl + F to search items by name and find corresponding chests they are found in.

First Circle#

Lethe#

Floor 1#

Chests:
1: 40K
2: Medical.i
3: 100K

Floor B1#

Chests
1: Reboot.i
2: Reanimator.i
3: S-Medical.i
4: Upgrade.i
5: Alchemy.i
6: Priest.prg
7: Rusty.ar
8: Medical.i

Floor B2#

Chests:
1: 90K
2: Traveller.bow
3: Bandages.opt
4: 45K
5: Alchemy.i

Other:
Key A000

Floor B3#

Chests: 1: Reanimator.i
2: Sulphur.dat
3: EarthTraveller.fit
4: 125K

Floor B4#

Backstage#

Chests: 1: Upgrade.i

Floor B5#

Chests: 1: Spectacles.opt
2: 80K
3: 142K
4: 45K
5: Timefold.prg
6: S-Medical.i

Backstage#

Chests: 1: Glass.prt
2: Null.dat
3: Upgrade.i
4: RoyalTraveller.fit
5: Alchemy.i
6: S-Medical.i
7: Plane.dat

Floor B6#

Backstage#

Chests: 1: Drone.prt
2: Sister.fit
3: Velvet.NPC
Note: I don't remember the exact extension of Velvet. Pretty sure she's a key item, though. You can only get her in your first cycle.

Crypt of Popes#

Styx#

Second Circle#

Dante#

Crypt of Beasts#

Virgil#

Third Circle#

Knossos#