The one-line path puzzle
Draw a single continuous line that connects the numbers 1, 2, 3 … in order and fills every cell on the board. Free, instant, unlimited — no registration required.
What is Trail?
Trail is a browser-based path puzzle in the same family as the LinkedIn Zip game. You draw one unbroken line that visits the numbered checkpoints in order — 1, then 2, then 3 — while passing through every single cell exactly once. Pure logic, a single solution, no guessing.
Unlike puzzles capped at one per day, Trail is unlimited — tap "New puzzle" any time, or take the shared Daily Challenge and build a streak.
How to play
- Press on 1 and drag your finger or mouse to trace a line.
- Pass through the numbers in order (1 → 2 → 3 → …).
- Your line must cover every cell and never cross itself.
- Drag backwards to undo, or tap a cell on the line to rewind.
Frequently asked questions
- Is Trail free?
- Yes — free and unlimited, supported by ads.
- Do I need an account?
- No — no sign-up and no registration needed. Your streak and best times are saved in your browser.
- Is every puzzle solvable?
- Yes — each board has exactly one valid path.
Tips to solve faster
Trail looks freeform, but it's pure deduction — there's exactly one path. A few habits make it click:
- Start at the corners. A corner has only two neighbours, so the line must pass straight through it — that often fixes connections instantly.
- Never strand a cell. Every cell must be visited; avoid moves that leave a cell with no way in or out.
- Plan each number segment. The stretch between two checkpoints has to cover a set region without blocking the next leg.
- Work edges inward. Borders have the fewest options, so committing them early narrows the middle.
Full walkthrough in the Trail strategy guide.