Every square is either cave (white) or rock (shaded). The cave must be one single connected area, and every rock square must be joined, through other rock, to the edge of the grid — there are no rocks floating in the middle of the cave.
Numbered squares are part of the cave. Each number counts the cave squares it can see in its row and column, itself included, looking until it meets rock or the edge.
Start with big numbers — they force long straight lines of cave — and small numbers, which stop the view early.
Shade the rock so the white squares form one connected cave, every rock joins the edge, and each number sees exactly that many cave squares.
The full guide, with a worked example and common mistakes: How to play Cave.
Each rock has to join the edge — through other rock squares or by touching the edge itself — but different rock areas don’t have to meet.
Yes — a 1 sees only itself, so all four of its neighbours are rock.
Yes — every puzzle here is checked to have exactly one solution.
Open the Cave Solver, type the numbers and press Solve.