Longest mate in King and Rook versus King and Rook endgame

Mate in 19

Also available in PGN notation.

White to move
Mate in 19 with Rh1+. Worse are Ka2, Kb1, Kb2, Rb1, Rc1, Rd1, Re2, Re3, Re4+, Re5, Re6, Re7, Re8, Rf1 and Rg1 which throw away the win.
1. Rh1+
White mates in 18 after Kg3, Kg4 and Kg5.
1... Kg4
Mate in 18 with Rg1+. Worse are Ka2, Kb1, Kb2, Rb1, Rc1, Rd1, Re1, Rf1, Rh2, Rh3, Rh4+, Rh5, Rh6, Rh7 and Rh8 which throw away the win.
2. Rg1+
White mates in 17 after Kf3, Kf4 and Kf5. Worse are Kh4 when White mates in 12, and Kh3 and Kh5 when White mates in 11.
2... Kf4
Mate in 17 with Rxg8. Worse are Ka2, Kb1, Kb2, Rb1, Rc1, Rd1, Re1, Rf1+, Rg2, Rg3, Rg4+, Rg5, Rg6, Rg7 and Rh1 which throw away the win.
3. Rxg8
White mates in 16 after Ke4 and Ke5. Worse are Kf3 and Kf5 when White mates in 15, and Ke3 when White mates in 14.
3... Ke5
Mate in 16 with Ka2, Kb1, Kb2, Ra8, Rd8, Re8+, Rg1 and Rg5+. Worse are Rb8, Rc8, Rf8, Rg2, Rg3, Rg4, Rg6, Rg7 and Rh8 with mate in 17.
4. Kb2
White mates in 15 after Kd4. Worse are Kd5, Kd6, Ke4, Ke6, Kf4, Kf5 and Kf6 when White mates in 14.
4... Kd4
Mate in 15 with Ka3, Kb3, Kc1, Kc2, Ra8, Rb8, Rc8, Rd8+, Re8, Rf8, Rg1, Rg2, Rg4+, Rg5 and Rh8. Worse are Ka2, Kb1, Rg3, Rg6 and Rg7 with mate in 16, and Ka1 with mate in 17.
5. Kc2
White mates in 14 after Ke4. Worse are Kd5 and Ke5 when White mates in 13, Kc5 when White mates in 12, and Kc4 and Ke3 when White mates in 11.
5... Ke4
Mate in 14 with Kc3, Kd2, Ra8, Rb8, Rc8, Re8+, Rg1, Rg4+ and Rh8. Worse are Kb3, Kc1, Kd1, Rd8, Rf8, Rg2, Rg3, Rg5, Rg6 and Rg7 with mate in 15, and Kb1 and Kb2 with mate in 16.
6. Kc3
White mates in 13 after Ke5. Worse are Kd5, Kf4 and Kf5 when White mates in 12, and Ke3 and Kf3 when White mates in 11.
6... Ke5
Mate in 13 with Kc4, Kd3, Ra8, Rb8, Re8+, Rg5+ and Rh8. Worse are Kb4, Kd2, Rc8, Rd8, Rf8, Rg1, Rg2 and Rg4 with mate in 14, Kb3, Kc2, Rg3, Rg6 and Rg7 with mate in 15, and Kb2 with mate in 16.
7. Re8+
White mates in 12 after Kf4 and Kf6. Worse are Kd5, Kd6 and Kf5 when White mates in 11.
7... Kf4
Mate in 12 with Kc4, Kd3, Kd4, Re1, Re2 and Re7. Worse are Kb3, Kb4, Kc2 and Kd2 with mate in 13, Kb2, Ra8, Rb8, Rc8, Rd8, Re6, Rf8+, Rg8 and Rh8 with mate in 14, and Re3, Re4+ and Re5 which throw away the win.
8. Kd3
White mates in 11 after Kf5. Worse are Kg5 when White mates in 10, Kg4 when White mates in 9, and Kf3 and Kg3 when White mates in 8.
8... Kf5
Mate in 11 with Kd4, Ke3 and Re4. Worse are Kc4, Ke2, Re1, Re2, Re3 and Re7 with mate in 12, Kc2, Kc3, Kd2, Ra8, Rb8, Rc8, Rd8, Rf8+, Rg8 and Rh8 with mate in 13, and Re5+ and Re6 which throw away the win.
9. Ke3
White mates in 10 after Kg5. Worse are Kf6 and Kg6 when White mates in 9, and Kg4 when White mates in 7.
9... Kg5
Mate in 10 with Ke4, Kf3, Re4, Re5+ and Rf8. Worse are Re6 and Re7 with mate in 11, Kd3, Kd4, Ke2, Kf2, Ra8, Rb8, Rc8, Rd8, Rg8+ and Rh8 with mate in 12, and Kd2 with mate in 13.
10. Rf8
White mates in 9 after Kg4. Worse are Kg6 and Kh6 when White mates in 8, Kh5 when White mates in 7, and Kh4 when White mates in 5.
10... Kg4
Mate in 9 with Rf4+. Worse are Kd3, Kd4, Ke4, Kf2, Rf1, Rf2, Rf3, Rf6 and Rf7 with mate in 10, Kd2, Ke2 and Re8 with mate in 11, Ra8, Rb8, Rc8, Rd8, Rg8+ and Rh8 with mate in 12, and Rf5 which throws away the win.
11. Rf4+
White mates in 8 after Kg5 and Kh5. Worse are Kg3 when White mates in 6, and Kh3 when White mates in 2.
11... Kg5
Mate in 8 with Kf3. Worse are Ke4 with mate in 9, Re4, Rf1, Rf2, Rf3, Rf7 and Rf8 with mate in 10, Ra4, Rb4, Rc4 and Rd4 with mate in 11, and Kd2, Kd3, Kd4, Ke2, Kf2, Rf5+, Rf6, Rg4+ and Rh4 which throw away the win.
12. Kf3
White mates in 7 after Kh5. Worse are Kg6 and Kh6 when White mates in 6.
12... Kh5
Mate in 7 with Rg4. Worse are Rf5+ with mate in 8, Ke2, Ke3, Ke4, Kf2, Kg2, Kg3, Ra4, Rb4, Rc4, Rd4, Re4, Rf6, Rf7 and Rf8 with mate in 9, and Rh4+ which throws away the win.
13. Rg4
White mates in 6 after Kh6.
13... Kh6
Mate in 6 with Ke3, Ke4, Kf4, Kg3, Rg1, Rg2 and Rg3. Worse are Kf2, Kg2 and Rg8 with mate in 7, Ke2 and Rf4 with mate in 8, Ra4, Rb4, Rc4, Rd4, Re4 and Rh4+ with mate in 9, and Rg5, Rg6+ and Rg7 which throw away the win.
14. Ke3
White mates in 5 after Kh5 and Kh7.
14... Kh5
Mate in 5 with Kf4. Worse are Kf3, Rg1, Rg2, Rg3, Rg7 and Rg8 with mate in 7, Rf4 with mate in 9, Ra4, Rb4, Rc4, Rd4 and Re4 with mate in 10, and Kd2, Kd3, Kd4, Ke2, Ke4, Kf2, Rg5+, Rg6 and Rh4+ which throw away the win.
15. Kf4
White mates in 4 after Kh6.
15... Kh6
Mate in 4 with Kf5. Worse are Ke3, Ke4, Ke5, Kf3, Kg3, Rg1, Rg2, Rg3, Rg5 and Rg8 with mate in 6, Rh4+ with mate in 10, and Rg6+ and Rg7 which throw away the win.
16. Kf5
White mates in 3 after Kh5 and Kh7.
16... Kh7
Mate in 3 with Kf6. Worse are Rg6 with mate in 4, Ke4, Ke5, Ke6, Kf4, Kg5, Rf4, Rg1, Rg2, Rg3 and Rg5 with mate in 5, Ra4, Rb4, Rc4, Rd4 and Re4 with mate in 6, Rh4+ with mate in 7, and Rg7+ and Rg8 which throw away the win.
17. Kf6
White mates in 2 after Kh8. Worse is Kh6 when White mates in 1.
17... Kh8
Mate in 2 with Kf7. Worse are Kg6, Ra4, Rb4, Rc4, Rd4, Re4, Rg6 and Rh4+ with mate in 3, Ke5, Ke6, Ke7, Kf5, Rf4, Rg1, Rg2, Rg3 and Rg5 with mate in 4, Kg5 with mate in 5, and Rg7 and Rg8+ which throw away the win.
18. Kf7
White mates in 1 after Kh7.
18... Kh7
Mate in 1 with Rh4#. Worse are Rg6 with mate in 2, Kf6, Ra4, Rb4, Rc4, Rd4, Re4, Rf4 and Rg5 with mate in 3, Ke6 and Ke7 with mate in 5, Rg3 with mate in 7, Rg1, Rg2, Rg7+ and Rg8 with mate in 8, and Ke8 and Kf8 with mate in 10.
19. Rh4#
Checkmate.
1-0


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