Dot Trail
Draw a single line from dot 1 through the dots in number order. It cannot cross itself or a wall, and it has to fill every square.
The rules
- 1Start on dot 1
The line always begins at dot 1. It is already drawn there when the puzzle opens.
- 2Drag to draw
Drag through squares next to the end of the line to extend it. Drag back over the line to take squares off again.
- 3Dots in order
The line must reach dot 2 before dot 3, and so on. A dot you are not due at yet simply refuses the step.
- 4Mind the walls
A thick bar between two squares is a wall. The line cannot cross it, and it cannot cross itself either.
- 5Fill every square
The puzzle is solved when the line covers the whole grid. Every board has exactly one line that manages it.
Controls
- Mouse / touch
- Drag from the end of the line to draw. Drag back over the line to shorten it.
- Keyboard
- Arrow keys move the end of the line one square, Backspace takes a square off, Ctrl+Z undoes.
Tips
- Corners are forced: a corner square has two neighbours, so the line has to come in one and leave by the other.
- Walls are gifts. A square with three walls has only one way in and out, which fixes that part of the route outright.
- Work backwards from the last dot as well as forwards from the first — the two ends usually meet in the middle.
- If a square would be left with no way out once the line passes by, the line has gone the wrong way. Back up a square or two.
Filling every square is the hard half: the dots say where to go, and the empty corners say how you are allowed to get there.
One line, drawn from dot 1, has to touch the numbered dots in number order and end up covering every square on the board. Walls block some of the steps, and the line may never cross itself, so the squares you are not thinking about decide the route as much as the dots are.
Common questions
How do you play Dot Trail?
Draw one continuous line that starts at dot 1, touches the numbered dots in order, never crosses itself or a wall, and ends up covering every square on the grid. Drag to draw it, or use the arrow keys.
Does the line really have to fill every square?
Yes, and that is the whole puzzle. Reaching the dots in order is usually easy; doing it by a route that leaves no square behind is what takes the thinking.
Is there only one solution?
Yes. Every board is generated from a known line, and walls are added until the solver can prove no other line fits, so you never have to guess between two answers that both look right.
Is Dot Trail like Zip?
It is the same family of puzzle: connect the numbers in order and fill the board. Dot Trail is our own build of it, with three grid sizes, a daily board that is the same for everyone, streaks and a leaderboard.