How to Play Patrol Route: One-Line Puzzle Techniques
Patrol Route has one rule: starting from the police station, drive down every street exactly once in a single unbroken route. It is easy to understand and surprisingly easy to get wrong, because one careless turn can cut off a corner of the map that you will never be able to reach again. This guide explains how the game works and the planning habits that let you solve even the eight-by-eight Chief maps without a hint.
The rules in detail
- The map is a grid of squares. Grey squares with a dot in the middle are streets; squares with a coloured roof are buildings and can never be entered.
- The route always begins at the square marked POLICE.
- It moves one square at a time up, down, left or right — never diagonally — and it can never visit the same square twice.
- The level is solved when the route has covered every street square. The Streets counter above the board shows how many you have covered so far.
- On maps with a checkered flag, the route must end on the flag. The game will not let you drive onto the flag until it is the very last street left.
Every map in the game was created from a real route that visits each street once, so a solution always exists. Many maps have several.
Controls
Press on the station, or on the end of your route, and drag through the streets. If your finger or mouse moves quickly across several squares, the route follows one square at a time, so you won't skip anything. To go back, drag back along the route, press Undo, or tap any square of your route to cut it back to that point. Restart clears the route completely.
On a keyboard, the arrow keys extend the route, U or Backspace undoes the last square, R restarts and H asks for a hint.
How hints and stars work
The Hint button compares your route with the solution stored for that map. If your route still matches it, the next square glows blue for a few seconds. If your route has already gone off course, the game cuts it back to the last square that matched and then shows the next one. Stars depend only on hints:
- 3 stars with no hints,
- 2 stars with one hint,
- 1 star with two or more.
There is no timer and no move limit, so undoing and experimenting is free. With 24 levels there are 72 stars to earn.
Technique 1: find the forced squares
The most useful habit is to look for street squares that have only one open neighbour — squares tucked into a corner or a pocket between buildings. Such a square can only be the start or the end of a route, because you can enter it but never leave again.
- If the dead end is the station itself, nothing special happens: you simply drive out of it.
- If it is anywhere else, it must be the last square of your route. Plan everything else so that you arrive there at the very end.
- If you ever create a second dead end, for example by driving past the mouth of a pocket, that route cannot be finished. Back up straight away.
Technique 2: sweep the edges early
Streets along the outside of the map and around buildings have fewer neighbours, so they are the easiest to cut off. Routes that follow the edge or run tightly around buildings early tend to leave the open middle of the map for later, where there is plenty of room to connect everything.
Technique 3: snake through open areas
A wide open block of streets is covered most safely with a back-and-forth "snake": along one row, step down, back along the next row, and so on. It leaves no gaps behind it. When the open area has an odd shape, snake through columns instead of rows, whichever leaves the exit where you need it.
Technique 4: plan flag maps backwards
From level 4 onwards some maps have a checkpoint flag. On these maps it helps to decide the last four or five squares before the flag first — which streets lead into it and how you will arrive there — and then connect the station to the start of that final stretch. The Chief maps near the end of the game all have a flag and up to 14 buildings, so this habit pays off.
A quick checklist before every move
- Does this move leave any street square with no way in?
- Does it create a new dead end that is not the last square?
- On flag maps, can I still reach the flag last?
If the answer to the first two is yes, or the third is no, choose a different direction.
Play it now
Start with the small Rookie maps and try to earn three stars on each before moving up; the techniques above become second nature quickly. If you like logic puzzles, Squad Car Escape offers 40 sliding-block puzzles, and our article on sliding-block puzzle techniques covers a similar "work backwards" way of thinking. Ready to plan the night shift? Play Patrol Route.