Level 270 solution

Solver-verified route

1. Place Piece 1 across column 5 row 4, column 6 row 4.
2. Place Piece 2 across column 5 row 5, column 6 row 5.
3. Place Piece 5 across column 7 row 5, column 8 row 5.
4. Place Piece 3 across column 3 row 1, column 4 row 1, column 5 row 1.
5. Place Piece 4 across column 2 row 1, column 2 row 2, column 2 row 3, column 2 row 4.
6. Place Piece 6 across column 2 row 5, column 2 row 6, column 2 row 7.
7. Place Piece 7 at column 3, row 2.

Part of the "Master columns" chapter. The solver certified 1000+ solving lines with 88% of in-between placements being dead ends, for a difficulty score of 20.1 (grade 5 of 5).