Solution to Challenge 2

Crease map (4 by 4 grid, centre twist)
- Grid lines around the centre four squares: valleys.
- Diagonals inside the centre four squares: mountains.

Steps
1. Draw the map and label every line V or M.
2. Pre-crease the whole grid, then the diagonals the other way.
3. Pinch the centre, rotate the middle square, and press flat.

Comparison
The finished fold should show a small turned square in the centre, surrounded by four triangles, matching the map line for line.

Checkpoint: the paper lies flat and no crease is the wrong way round.