The Numbered Arch

An arch is cut across the passage and carved above it, deeply and well, is the number 4. There is no 3 anywhere behind you and no 5 anywhere ahead. Somebody has added a small careful question mark beside it in charcoal, and somebody else has rubbed most of that away.

Depth 2

You are reading the dungeon, not walking it. Rooms are only created by people, and only from inside the maze.