How to play Cave
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. Also known as Corral, Bag puzzle, Cave puzzle.
The rules
- Every square is cave (white) or rock (shaded).
- All cave squares form one connected area.
- Every rock square is joined to the edge of the grid through other rock squares.
- Each number is a cave square that sees exactly that many cave squares across and down, itself included, until rock or the edge.
Playing Cave on Puzzle Solvers
- Choose a size and a difficulty, then press New Puzzle.
- Tap a square to make it rock, again for a dot (cave), again to clear. Drag to do several.
- When the grid is full, numbers turn green if they see the right amount and red if not.
- Hint explains the next deduction — what each number must see, keeping the cave in one piece and every rock on the edge.
Using the Cave solver
- Choose the size and type the numbers (or press Sample).
- Press Solve and step through: what numbers must see, one cave, and rock joined to the edge.
A worked example
An 11 in a 7×7 grid can see at most 13 squares, so at most two of its line are rock — the squares next to it are usually cave.
A 1 means all four neighbours are rock (or the edge) — and each of those rocks must still reach the edge.
Strategies
- Must see. If a number can’t reach its total without looking one way, it must see at least some squares that way.
- Seen enough. Once a number sees its total, the next square in each direction is rock.
- One cave. A square whose rock would split the cave must be cave.
- Rock to the edge. A rock square boxed in by cave can’t be — follow the rock to the edge.
- Corners. A 2 in a corner sees one more square: one direction is blocked straight away.
Common mistakes
- Leaving a rock surrounded by cave in the middle of the grid.
- Counting past a rock square when counting what a number sees.
- Forgetting to count the number’s own square.
Where it comes from
Cave puzzles appeared in Japanese and European puzzle magazines in the 1990s and are a classic of puzzle championships.
Frequently asked questions
Do rocks have to touch each other?
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.
Does a number count itself?
Yes — a 1 sees only itself, so all four of its neighbours are rock.
Is there always one answer?
Yes — every puzzle here is checked to have exactly one solution.
How do I solve one from a book?
Open the Cave Solver, type the numbers and press Solve.
Keep going
- Play Cavea fresh puzzle every time
- Cave Solverstep by step, every move explained
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- Tap ShadeShade one connected wall so that every clue lists the runs of shaded squares…
All guides: How to play every puzzle and game.