Train Track Logic Unblocked

Train Track Logic asks you to finish a railway that someone started and abandoned. Its endpoints, labelled A and B, are shown, and a handful of rails were laid before you arrived. Clues above the grid and down its right side give the exact number of track squares for every column and row. You must join A and B with a single route that agrees with all of them. It is James Harvey’s Tracks puzzle from Simon Tatham’s collection, and here you can play it unblocked in any browser.

Laying the Line

The line comes in through A on the west side and leaves through B along the southern edge. In between, every piece is either a straight or a right-angle bend. It cannot branch, cross itself or loop around.

Each clue counts squares that contain any track, whether that is a straight or a curve. Pieces printed at the start always belong to the final answer.

Clicking the border shared by two neighbouring squares puts rails across it and links them. A right-click on that border crosses it off instead. Clicking in the middle of a square places a colored note that says some track goes through, and right-clicking places a cross for an empty square. Sweeping across several squares notes a whole stretch at once. Overfilled lines show their clue in red, and a finished railway makes the board flash.

Train Track Logic controls

To do this	Keyboard	Mouse	Touch
Lay rails across an edge	Move onto an edge with the arrows, then Enter	Left-click the edge between two squares	Tap the edge with Tap set to Track
Cross out an edge	Space on an edge	Right-click the edge	Press and hold the edge, or switch Tap to Cross
Note a square as track or no track	Enter or Space on a square	Left-click or right-click inside the square	Tap or press and hold inside the square
Mark a run of squares at once	—	Left- or right-drag across them	Drag, holding first for crosses
New puzzle, undo, redo	N, U, R	Buttons above the grid	Buttons above the grid

How to Think Like a Track Planner

Settle the extremes. A row or column with a 0 has no track at all. One whose clue equals its full length is track from end to end. Mark both kinds before anything else.

Two edges per square. Any square carrying rail connects through precisely two sides. Once you have crossed out two edges, the remaining two are the rails. Once two are railed, cross out the rest.

Follow the given pieces. Each pre-placed rail aims at a neighbour, and that neighbour needs rail too. Extend each one as far as the logic allows.

Fill a finished line with crosses. Once a row hits its number, drag crosses across its leftover squares. It keeps the board readable and stops accidental extra track.

Watch out for closed circuits. A loop can satisfy local counts but never connects A and B. If two route segments are about to meet, check that they aren’t the same segment.

Plan the turns. If the track must reach a far column, it has to curve toward it somewhere. Counting the turns you need narrows where they can go.

Why It Stands Out

Train Track Logic feels more physical than most number grids. You are drawing an actual route, so mistakes are easy to see, and the satisfaction of watching the line snake across the map is real. A dozen presets go from 8x8 all the way to 15x15, and custom sizes exist for anything else.

If you like path puzzles, Pearl Loop Puzzle builds a closed ring instead of an open line. For pipe-connecting fun, try Net Pipe Puzzle.