The puzzle asks for one railway between two endpoints. The numbers outside the grid tell you how many squares in each row and column belong to that railway. You are counting occupied squares, including corners and endpoints.
Start with what is certain.
A zero clue rules out every square in that line. A clue equal to the line’s length fills the whole line. Once the number of placed tracks reaches a clue, the remaining squares in that row or column are empty. Use those facts to narrow the next row or column.
Keep the route connected.
Matching the numbers is only part of the job. Rails must make a continuous trip from the entrance to the exit. They cannot split into branches or leave a separate loop behind. When a route approaches a corner, look ahead before committing to a turn.
Playing on a phone.
Oakever’s Google Play listing describes double-tapping to lay track, tapping to mark an X, and swiping to connect, with three mistakes per attempt. The mobile game progresses from 4×4 to 12×12 boards. See the official game listing for the current version.
Playing in our practice yard.
Select ? to mark a track square while leaving its direction undecided. Choose one of the six rail shapes, then tap a square to place it. Drag through adjacent squares to connect a route along your stroke. Select Empty to mark ×, or Erase to clear a choice. On a keyboard, Tab to a square, use arrow keys to move, and press Enter or Space to act. A stroke only sets the directions you actually draw; its unfinished ends remain open.
A and B are fixed endpoints. Blue given rails are also fixed. Green numbers count occupied track squares; winning also requires every rail direction to form one connected route. A wrong square or direction costs a mistake. Undo reverses a tap or stroke without restoring mistakes or hints. After three mistakes, reset and try again. Each attempt allows three hints.
Your practice progress.
There are 24 original puzzles across six grid sizes: 4×4, 5×5, 6×6, 7×7, 8×8 and 10×10. Choose Starter through Expert in the puzzle menu, or use Try Expert for a direct jump. Your current board, rail directions and completed puzzles are saved in this browser when local storage is available. These boards do not reproduce numbered levels from the mobile app.
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