Thursday, 25 April 2013

Queen vs Minor Pieces Fortress Part 2, Bishop and Knight

Previous : Queen vs Minor Pieces Fortress Part 1 - Two Bishops

Bishop and Knight alone can not hold the position against queen except one position, which can be arranged on two corner of the board, depending upon which colour bishop you have.

Bishop and Knight fortress



As you can see that white king can not enter into the squares marked with green colour. Therefore Bishop can not be captured so position remains draw. Moreover, white is not able to force black into zugzwang. Please note that attacker positions (here white's King and Queen) are irrelevant once defender gets the given position.

Originally position was studied by Max A.K.S. Karstedt in 1903 who has also discovered some other possibilities in Philidor position even but not popular because they are complicated.

Karstedt Position - 1903




1. Qf5 Kh8 2. Ke7 Kg8 3. Qc2 Kh8 4. Qc8+ Kh7 5. Qa8 Ng6+ 6. Ke6 Ne5 7. Qh1+ Kg8 and position remains the same.However here are some moves which are played by computer (F-13) with no result. 8. Qd5 Kh7 9. Kf5 Kh8 10. Qa8+ Kh7 11. Qb7 Kg8 12. Qe7 Kh7 13. Qe6 Bh8 14. Ke4 Bg7 15. Kd5 Bh8 16. Kd6 Bg7 17.Qd5 Kh8 18. Qe4 Kg8 19. Ke6 Kh8 20. Kd5 Kg8 21. Qf5 Bh8 22. Qc8+ Kh7 23. Qd8 Ng6



Monday, 22 April 2013

Queen vs Minor Pieces Fortress Part 1


In this article we will see different fortress positions for minor pieces (usually Defender Side) against Queen in pawn less endgame.

Queen vs. Two Bishops

Bishop must be arrange in a way so that stronger side king can not attack them. You can set up the fortress in 4 corners.

Giambattista Lolli has given following position in his book Osservazioni teorico-pratiche sopra il giuoco degli scacchi (English: Theoretical-practical views on the game of chess), published 1763 in Bologna. Which has been used in almost every chess endgame book to describe fortress against queen for two bishops.

Two Bishop Fortress


1.Qd7+ Kg8 2.Qe6+ Kg7 3.Qd6 Bf7 4.Kf5


and again with 4.... Bg6+ 5.Kf4 and Black again gets Lolli Position. and there is no another way to win this game for white. You can your self analyse the position or can take help of computer in case you have any doubts. 5...Kf7 6.Qd7+ Kf8 =:=

In the next part we will  see fortress for two knights.