Number Trail is a number path puzzle. Draw a single trail that visits every cell of the grid exactly once, passing the numbers in order and finishing on the last one. Start on 1 and drag, tap the next cells, or use the arrow keys. The trail moves up, down, left or right, never diagonally, and thick bars are walls it cannot cross.
Dragging back over the trail erases it, and pressing any cell on the trail cuts it back to that point so you can carry on from there. Undo removes a whole stroke. A move that breaks the rules is refused with a short reason, such as reaching a number too early or hitting a wall. If an empty cell can no longer be filled, it gets a red outline, so you know to drag back.
Every grid has exactly one solution. A clock runs from your first move and your fastest hint-free time is saved, but time does not affect stars. Solve with no hint and no more than three undos for three stars; up to two hints gives two. The hint fixes any wrong part of the trail and draws the next correct steps. Sixty grids grow from 5×5 to 9×9 across five tiers, from First Steps to Summit, with a daily grid.
Worked example
A corner cell has only two neighbours. Unless it holds 1 or the final number, the trail must come in through one of them and leave through the other. The same goes for any cell that walls leave with just two open sides. Draw those short pieces first, and the rest of the path often follows.
Strategy tips
Mind the corners. Plan how the trail will sweep through each corner before it gets close.
Watch the numbers ahead. The trail must reach the next number without touching a later one.
Do not strand cells. A pocket of empty cells cut off from the trail can never be filled.