White begins by taking control of the 4th rank (for example, by moving the h1 rook to h4). The black king is now cut off from half the board. After black’s move, white moves the other rook to the fifth rank, forcing the black king to move towards the edge of the board opposite white’s king.
If the black king prevents white from advancing a rook, such as by moving to g6, white will transfer the rook across the board, placing it on the file next to the other rook, such as on b4.
White continues delivering safe checks and forcing the black king “up the ladder” to the back rank. White delivers checkmate with one rook on the seventh rank and one rook on the eighth rank. Note that white does not have to move his/her own king in this exercise.
