E1 — Boulder-Filled Passage

51 — Boulder-Filled Passage

Large rocks and boulders have been placed here in order to seal off this tunnel. It will take 100 man-turns to open a way large enough for a human to pass through into the area beyond. (You have the option of allowing this passage to lead to the outside somewhere to the southwest of the Caves of Chaos, or you may choose to have it go all the way to the Cave of the Unknown. If you opt for the latter case, you must, of course, prepare an appropriate underground area map and stock it with monsters and treasures.)

Source: B2, PDF page 26. Original mechanics retained.