Longest mate in King and Rook versus King endgame

Mate in 16

Also available in PGN notation.

White to move
Mate in 16 with Kg7, Kg8, Kh7, Rb4+, Rb5, Rb8, Rd3 and Rh3. Worse are Ra3, Rb1, Rb2, Rb6, Rb7 and Rc3 with mate in 17, and Re3, Rf3+ and Rg3 which throw away the win.
1. Kg7
White mates in 15 after Ke5. Worse are Ke4 when White mates in 14, Kf5 and Kg4 when White mates in 13, and Kg5 when White mates in 11.
1... Ke5
Mate in 15 with Kf7, Kg6, Ra3, Rb1, Rb4, Rb5+, Rb7, Rb8, Rd3 and Rh3. Worse are Kf8, Kg8, Kh6, Kh7, Rb2, Rb6, Rc3, Re3+, Rf3 and Rg3 with mate in 16, and Kh8 with mate in 17.
2. Rb4
White mates in 14 after Kf5. Worse are Kd5 when White mates in 13, and Kd6 and Ke6 when White mates in 12.
2... Kf5
Mate in 14 with Ra4 and Rh4. Worse are Kf7, Kf8, Kg8, Kh6, Kh7, Rb5+, Rb8, Rc4 and Rd4 with mate in 15, Kh8, Rb1, Rb2, Rb3, Rb6 and Rb7 with mate in 16, and Re4, Rf4+ and Rg4 which throw away the win.
3. Ra4
White mates in 13 after Ke5. Worse are Kg5 when White mates in 12, and Ke6 when White mates in 11.
3... Ke5
Mate in 13 with Kg6. Worse are Kf7, Kf8 and Rh4 with mate in 14, Kg8, Kh6, Kh7, Kh8, Ra1, Ra2, Ra3, Ra5+, Ra6, Ra7, Ra8, Rb4, Rc4 and Rg4 with mate in 15, and Rd4, Re4+ and Rf4 which throw away the win.
4. Kg6
White mates in 12 after Kd5 and Kd6. Worse is Ke6 when White mates in 11.
4... Kd5
Mate in 12 with Kf5 and Kf6. Worse are Kf7, Kg5, Kg7, Ra8, Rb4, Rf4, Rg4 and Rh4 with mate in 14, Kh5, Kh6, Kh7, Ra1, Ra2, Ra3, Ra5+, Ra6 and Ra7 with mate in 15, and Rc4, Rd4+ and Re4 which throw away the win.
5. Kf6
White mates in 11 after Kc5. Worse are Kc6 and Kd6 when White mates in 10.
5... Kc5
Mate in 11 with Ke6. Worse are Ke5, Kf5, Re4, Rf4, Rg4 and Rh4 with mate in 12, Ke7 and Kf7 with mate in 13, Kg5, Kg6, Kg7, Ra1, Ra2, Ra3, Ra5+, Ra6, Ra7 and Ra8 with mate in 14, and Rb4, Rc4+ and Rd4 which throw away the win.
6. Ke6
White mates in 10 after Kb5. Worse are Kc6 when White mates in 9, and Kb6 when White mates in 8.
6... Kb5
Mate in 10 with Rd4, Re4, Rf4, Rg4 and Rh4. Worse are Ra1, Ra2, Ra3, Ra7 and Ra8 with mate in 13, and Kd5, Kd6, Kd7, Ke5, Ke7, Kf5, Kf6, Kf7, Ra5+, Ra6, Rb4+ and Rc4 which throw away the win.
7. Rh4
White mates in 9 after Kc5. Worse are Ka5, Kb6 and Kc6 when White mates in 8, and Ka6 when White mates in 7.
7... Kc5
Mate in 9 with Re4, Rf4 and Rg4. Worse are Ke5 and Ra4 with mate in 11, Ke7, Kf5, Kf6 and Kf7 with mate in 12, Kd7, Rh1, Rh2, Rh3, Rh5+, Rh6, Rh7 and Rh8 with mate in 13, and Rb4, Rc4+ and Rd4 which throw away the win.
8. Rg4
White mates in 8 after Kb6 and Kc6. Worse is Kb5 when White mates in 7.
8... Kc6
Mate in 8 with Rg5. Worse are Ke5, Rb4, Rc4+, Rd4, Re4, Rf4, Rg1, Rg2, Rg3, Rg6, Rg7, Rg8 and Rh4 with mate in 10, Ra4 with mate in 11, and Ke7, Kf5, Kf6 and Kf7 with mate in 12.
9. Rg5
White mates in 7 after Kc7. Worse are Kb7 when White mates in 6, and Kb6 when White mates in 5.
9... Kc7
Mate in 7 with Rc5+. Worse are Kd5, Ke7, Re5, Rf5 and Rh5 with mate in 8, Ra5, Rb5, Rd5, Rg1, Rg2, Rg3, Rg4, Rg6, Rg7+ and Rg8 with mate in 9, Ke5, Kf6 and Kf7 with mate in 10, and Kf5 with mate in 11.
10. Rc5+
White mates in 6 after Kb6, Kb7 and Kb8. Worse is Kd8 when White mates in 2.
10... Kb7
Mate in 6 with Kd7. Worse are Kd5, Kd6 and Ke7 with mate in 7, Ke5, Re5, Rf5, Rg5 and Rh5 with mate in 8, Ra5, Rb5+, Rc1, Rc2, Rc3, Rc4 and Rd5 with mate in 9, Kf5, Kf6 and Kf7 with mate in 10, and Rc6, Rc7+ and Rc8 which throw away the win.
11. Kd7
White mates in 5 after Kb6. Worse are Kb8 when White mates in 4, Ka7 when White mates in 3, and Ka6 and Ka8 when White mates in 2.
11... Kb6
Mate in 5 with Rd5, Re5, Rf5, Rg5 and Rh5. Worse are Kd6 with mate in 6, Rc6+ with mate in 10, Rc1, Rc2, Rc3, Rc4, Rc7 and Rc8 with mate in 11, and Kc8, Kd8, Ke6, Ke7, Ke8, Ra5 and Rb5+ which throw away the win.
12. Rh5
White mates in 4 after Kb7. Worse are Ka7 when White mates in 3, and Ka6 when White mates in 2.
12... Kb7
Mate in 4 with Rh6. Worse are Rb5+ with mate in 5, Kd6, Ra5, Rc5, Rd5, Re5, Rf5, Rg5, Rh1, Rh2, Rh3, Rh4, Rh7 and Rh8 with mate in 6, and Kd8, Ke6, Ke7 and Ke8 with mate in 8.
13. Rh6
White mates in 3 after Ka8 and Kb8. Worse is Ka7 when White mates in 2.
13... Kb8
Mate in 3 with Kc6. Worse are Rb6+ with mate in 4, Kd6, Kd8, Ra6, Rc6, Rd6, Re6, Rf6, Rg6, Rh1, Rh2, Rh3, Rh4, Rh5, Rh7 and Rh8+ with mate in 5, and Ke6, Ke7 and Ke8 with mate in 7.
14. Kc6
White mates in 2 after Ka7 and Ka8. Worse is Kc8 when White mates in 1.
14... Ka8
Mate in 2 with Kb6. Worse are Kc7, Rh1, Rh2, Rh3, Rh4, Rh5 and Rh8+ with mate in 3, Rd6, Re6, Rf6, Rg6 and Rh7 with mate in 4, Kd6 and Kd7 with mate in 5, Kb5 and Kc5 with mate in 6, and Kd5 with mate in 8.
15. Kb6
White mates in 1 after Kb8.
15... Kb8
Mate in 1 with Rh8#. Worse are Rc6 with mate in 2, Kc6, Rd6, Re6, Rf6, Rg6, Rh1, Rh2, Rh3, Rh4 and Rh5 with mate in 3, Kc5 with mate in 7, Rh7 with mate in 8, Kb5 with mate in 11, and Ka5 and Ka6 with mate in 12.
16. Rh8#
Checkmate.
1-0


An endgame analysis by Joe Leslie-Hurd on 16 February 2005.