Detailed description

Five drawings of the 9 towers of the Willis building. Each tower occupies one square of a 3 by 3 square grid.

  1. two 50-storey towers highlighted brown. Label reads '50 floors'
  2. two 66-storey towers highlighted pink. Label reads '66 floors'
  3. three 90-storey towers highlighted yellow. Label reads '90 floors'
  4. two 108-storey towers highlighted green. Label reads '108 floors'
  5. All 9 towers colour-coded