Fog over the Locks — Daily puzzle for 2026-11-05

Medium — logic-grid deduction puzzle

Petra, Sami, Wren, Goran and Vera spent a foggy November week mending the old canal's locks while it was closed to boats for the winter.

In November, the old canal on the hill closed to boats for the winter. Its locks climb the slope one after another, like a staircase made of water, from the first lock at the bottom to the fifth at the top, and now the water was let out of every one of them. The days were short and foggy, there was frost on the towpath, and the last brown leaves were falling from the nearly bare trees. Petra, Sami, Wren, Goran and Vera pulled on wool hats and thick gloves and went to work, each at a different lock. Each keeper pulled out the rotten planks, fitted new ones of a different wood, and wrote down the one problem that had kept that lock from working. Then a gust of wind blew the notebook pages across the wet grass. Now the harbourmaster wants to know who mended which lock, which wood went in, and what was wrong.

Clues

1. The leak turned up higher up the hill than the rust, but lower down than the jam.
2. Petra fitted one of the beech and the pine, and Goran fitted the other.
3. The ash went into the lock two above the one fitted with beech.
4. One of Sami and Vera found the rust, and the other found the jam.
5. The crack was found in the very next lock up from the leak.
6. Goran worked exactly three locks higher up than whoever cleared the silt.
7. Sami's lock sat three locks below the one where the elm went in.

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