The finished wall on an oak desk next to a laptop and a mug of tea, the red tower at the front left and the teal tower behind

Great Wall Path Puzzle

Turn nine squares of wall until one walkway runs from the red tower to the teal one.

Start with the empty tray: 9 engraved squares, numbered, with an N arrow at the top edge.

A challenge fixes a few squares first. This one sets both towers and two corners, each in its square and turned its own way.

The other five go in. S is in the right square but facing backwards: its walkway meets A one level too high.

Lift it clear, give it a half turn, set it down. Now its ramp steps down to A and up to B.

Follow the walkway from the red tower. It runs through all 9 squares to the teal one, with no dead end and no loop.

That is one setup of 14. The next starts from different fixed squares, and the route takes a different shape.

Every walkway arrives at a height.

Each square carries a stretch of wall whose walkway leaves by one or two edges, low, middle or high. Two squares join only where both edges carry walkway at the same height. Turning a square a quarter turn moves its exits round; it never changes their heights.

There are 3 straight runs, 4 corners and 2 towers. Most of them climb or drop a level on the way through, which is why a square that points the right way can still be wrong.

low middle high, as the walkway leaves that edge

Up close

The solved puzzle held level in two open hands over a kitchen table — It sits in two hands with room to spare: 6.9 × 7.2 × 2.5 in, tray and all.

Close on the red tower, the stepped green ramp beside it and the teal tower behind — The red tower is where every route starts. The green ramp beside it climbs to the highest walkway.

The solved board from above one corner, every square seated in the slate tray — Solved, it stays out as a small model of the wall: cream ramparts, green hillsides, two towers.

Great Wall Path Puzzle

Turn nine squares of wall until one walkway runs from the red tower to the teal one.

Size: 6.9 × 7.2 × 2.5 in, every square in its tray
Weight: 9.5 oz
Pieces: 9 wall squares, 2 of them towers, and a numbered tray with an N arrow
Puzzles: 14 challenge setups, from a starter to the open board
Material: PLA
Power: None needed

Good to know

How do I win?: Start the walkway at the red tower and finish at the teal one, passing through all 9 squares. Wherever two walkways meet they have to line up and sit at the same height. A dead end or a separate loop does not count.
How many puzzles are in it?: 14 challenge setups. Each one fixes a few squares in a set place and turn, and you work out the rest. A starter setup leaves just 2 squares to place.
Do the squares lock in?: No. Engraved lines and numbers on the tray show where each square goes, and the squares lift straight out. Keep the tray level and lift a square clear of its neighbours before you turn it.
Does it need batteries?: No. There is nothing to power: 9 squares of wall and the tray they sit in.
What is it made of?: PLA, in the colours you see: cream and sand ramparts, three shades of green hillside, one brick-red tower, one teal tower, on a dark slate tray.