O.T. Bláthy  Cyril Banderier
Checkmate in 290 moves., 1929
This problem is the longest checkmate problem, due to the great componist
Ottó Bláthy.
The position is not legal (easy retroanalysis),
and it is easy to convert it to a legal position, but I give the original Bláthy position. Bláthy won
a prize for this position, in 1929. The analysis/solution given here
was done by Cyril Banderier, in
1992 (and is online since 1998). Don't deduce from this date it took
me more than 63 years to solve this problem ;) 1.Rd1+
Bd4 2.c4+ Kd6
3.Rxg1 Bc3 4.Rd1+
Bd4 OK the Zugzwang is in place, now white
has to find how to use it. The idea is to play Kb6 WHEN black's bishop is in a8, then black can only
plays its pawns (b2,h7,h6,h2) and white hopes to capture them and at the end hopes also to capture Bb7
and to mate ?!? Let's go on and see: 5.Ka5 Bb7
6.Ka4 Ba8 7.Ka3
Bb7 8.Ka2 Ba8
9.Kb1 Bb7 10.Kc2
Ba8 11.Kd3 Bb7 The
funny thing is that is not possible to leave the e3 pawn, because of a quick mate (e2 chekmates in e5,
with the rook sticking the bishop in d4.) 12.Re1 Now
comes the great trick : White has to lost one time in order to get Kb6 when black's bishop is in a8. 12...Ba8
13.Rf1! Bb7 14.Rd1
Ba8 15.Kc2 Bb7
16.Kb1 Ba8 17.Ka2
Bb7 18.Ka3 Ba8
19.Ka4 Bb7 20.Ka5
Ba8 21.Kb6 h4 You
got it, simply repeat this Zugzwang sequence until black has no more moves. 22.Ka5
Bb7 23.Ka4 Ba8
24.Ka3 Bb7 25.Ka2
Ba8 26.Kb1 Bb7
27.Kc2 Ba8 28.Kd3
Bb7 29.Rf1 Ba8
30.Re1 Bb7 31.Rd1
Ba8 32.Kc2 Bb7
33.Kb1 Ba8 34.Ka2
Bb7 35.Ka3 Ba8
36.Ka4 Bb7 37.Ka5
Ba8 38.Kb6 h3
39.Ka5 Bb7 40.Ka4
Ba8 41.Ka3 Bb7
42.Ka2 Ba8 43.Kb1
Bb7 44.Kc2 Ba8
45.Kd3 Bb7 46.Rf1
Ba8 47.Re1 Bb7 If
during the game, black plays Be5, dont take the bishop, go on the Zugzwang. The scheme Kb6 and pawn checkmating
with b4xc5+ is usefull in some positions. 48.Rd1
Ba8 49.Kc2 Bb7
50.Kb1 Ba8 51.Ka2
Bb7 52.Ka3
Ba8 53.Ka4
Bb7 54.Ka5
Ba8 55.Kb6
h2 56.Ka5
Bb7 57.Ka4
Ba8 58.Ka3
Bb7 59.Ka2
Ba8 60.Kb1
Bb7 61.Kc2
Ba8 62.Kd3
Bb7 63.Rf1
Ba8 64.Re1
Bb7 65.Rd1
Ba8 66.Kc2
Bb7 67.Kb1
Ba8 68.Ka2
Bb7 69.Ka3
Ba8 70.Ka4
Bb7 71.Ka5
Ba8 72.Kb6
h5 73.Ka5
Bb7 74.Ka4
Ba8 75.Ka3
Bb7 76.Ka2
Ba8 77.Kb1
Bb7 78.Kc2
Ba8 79.Kd3
Bb7 80.Rf1
Ba8 81.Re1
Bb7 82.Rd1
Ba8 83.Kc2
Bb7 84.Kb1
Ba8 85.Ka2
Bb7 86.Ka3
Ba8 87.Ka4
Bb7 88.Ka5
Ba8 89.Kb6
h4 90.Ka5
Bb7 91.Ka4
Ba8 92.Ka3
Bb7 93.Ka2
Ba8 94.Kb1
Bb7 95.Kc2
Ba8 96.Kd3
Bb7 97.Rf1
Ba8 98.Re1
Bb7 99.Rd1
Ba8 100.Kc2
Bb7 101.Kb1
Ba8 102.Ka2
Bb7 103.Ka3
Ba8 104.Ka4
Bb7 105.Ka5
Ba8 106.Kb6
h3 107.Ka5
Bb7 108.Ka4
Ba8 109.Ka3
Bb7 110.Ka2
Ba8 111.Kb1
Bb7 112.Kc2
Ba8 113.Kd3
Bb7 114.Rf1
Ba8 115.Re1
Bb7 116.Rd1
Ba8 117.Kc2
Bb7 118.Kb1
Ba8 119.Ka2
Bb7 120.Ka3
Ba8 121.Ka4
Bb7 122.Ka5
Ba8 123.Kb6
h6 124.Ka5
Bb7 125.Ka4
Ba8 126.Ka3
Bb7 127.Ka2
Ba8 128.Kb1
Bb7 129.Kc2
Ba8 130.Kd3
Bb7 131.Rf1
Ba8 132.Re1
Bb7 133.Rd1
Ba8 134.Kc2
Bb7 135.Kb1
Ba8 136.Ka2
Bb7 137.Ka3
Ba8 138.Ka4
Bb7 139.Ka5
Ba8 140.Kb6
h5 141.Ka5
Bb7 142.Ka4
Ba8 143.Ka3
Bb7 144.Ka2
Ba8 145.Kb1
Bb7 146.Kc2
Ba8 147.Kd3
Bb7 148.Rf1
Ba8 149.Re1
Bb7 150.Rd1
Ba8 151.Kc2
Bb7 152.Kb1
Ba8 153.Ka2
Bb7 154.Ka3
Ba8 155.Ka4
Bb7 156.Ka5
Ba8 157.Kb6
h4 158.Ka5
Bb7 159.Ka4
Ba8 160.Ka3
Bb7 161.Ka2
Ba8 162.Kb1
Bb7 163.Kc2
Ba8 164.Kd3
Bb7 165.Rf1
Ba8 166.Re1
Bb7 167.Rd1
Ba8 168.Kc2
Bb7 169.Kb1
Ba8 170.Ka2
Bb7 171.Ka3
Ba8 172.Ka4
Bb7 173.Ka5
Ba8 174.Kb6
h1=Q 175.Rxh1
Bg7 176.Rd1+
Bd4 177.Ka5
Bb7 178.Ka4
Ba8 179.Ka3
Bb7 180.Ka2
Ba8 181.Kb1
Bb7 182.Kc2
Ba8 183.Kd3
Bb7 184.Rf1
Ba8 185.Re1
Bb7 186.Rd1
Ba8 187.Kc2
Bb7 188.Kb1
Ba8 189.Ka2
Bb7 190.Ka3
Ba8 191.Ka4
Bb7 192.Ka5
Ba8 193.Kb6
h2 194.Ka5
Bb7 195.Ka4
Ba8 196.Ka3
Bb7 197.Ka2
Ba8 198.Kb1
Bb7 199.Kc2
Ba8 200.Kd3
Bb7 201.Rf1
Ba8 202.Re1
Bb7 203.Rd1
Ba8 204.Kc2
Bb7 205.Kb1
Ba8 206.Ka2
Bb7 207.Ka3
Ba8 208.Ka4
Bb7 209.Ka5
Ba8 210.Kb6
h3 211.Ka5
Bb7 212.Ka4
Ba8 213.Ka3
Bb7 214.Ka2
Ba8 215.Kb1
Bb7 216.Kc2
Ba8 217.Kd3
Bb7 218.Rf1
Ba8 219.Re1
Bb7 220.Rd1
Ba8 221.Kc2
Bb7 222.Kb1
Ba8 223.Ka2
Bb7 224.Ka3
Ba8 225.Ka4
Bb7 226.Ka5
Ba8 227.Kb6
h1=Q 228.Rxh1
Bg7 229.Rd1+
Bd4 230.Ka5
Bb7 231.Ka4
Ba8 232.Ka3
Bb7 233.Ka2
Ba8 234.Kb1
Bb7 235.Kc2
Ba8 236.Kd3
Bb7 237.Rf1
Ba8 238.Re1
Bb7 239.Rd1
Ba8 240.Kc2
Bb7 241.Kb1
Ba8 242.Ka2
Bb7 243.Ka3
Ba8 244.Ka4
Bb7 245.Ka5
Ba8 246.Kb6
h2 247.Ka5
Bb7 248.Ka4
Ba8 249.Ka3
Bb7 250.Ka2
Ba8 251.Kb1
Bb7 252.Kc2
Ba8 253.Kd3
Bb7 254.Rf1
Ba8 255.Re1
Bb7 256.Rd1
Ba8 257.Kc2
Bb7 258.Kb1
Ba8 259.Ka2
Bb7 260.Ka3
Ba8 261.Ka4
Bb7 262.Ka5
Ba8 263.Kb6
h1=Q 264.Rxh1
Bg7 265.Rd1+
Bd4 266.Ka5
Bb7 267.Ka4
Ba8 268.Ka3
Bb7 269.Ka2
Ba8 270.Kb1
Bb7 271.Kc2
Ba8 272.Kd3
Bb7 273.Rf1
Ba8 274.Re1
Bb7 275.Rd1
Ba8 276.Kc2
Bb7 277.Kb1
Ba8 278.Ka2
Bb7 279.Ka3
Ba8 280.Ka4
Bb7 281.Ka5
Ba8 282.Kb6
Bb7


[282...b1=Q 283.Rxb1
Bc3 284.Rd1+
Bd2

 
(284...Bd4 285.b4
Rxb8+ 286.axb8=Q
cxb4+ 287.Rxd4#) 

285.Rxd2+ exd2
286.e4 Rxb8+
287.axb8=Q d1=Q
288.e5#] 
283.Kxb7 b1=Q


[283...Rxb8+ 284.axb8=Q
b1=Q 285.Qxd8#] 
284.Rxb1 Be5
285.Rd1+ Bd4
286.Rxd4+ cxd4
287.Kb6 d3
288.a8=Q Rxb8+
289.Qxb8 dxe2
290.Qxd8#
If you are aware of any longer mate
problem or if you find any reference to Bláthy's problem in the literature, tell it ! I'm only aware
of an article by François Le Lionnais about Chess in the french "Encyclopedia Universalis"
which gives the initial position, but not its solution. Note that with endgame databases / bruteforce
analysis of computers, it was shown that the deepest checkmate with 5 pieces is a 262 moves mate with K+N+N vs K+R,
a 267 moves mate with 6 pieces, and, in 2006,
Marc Bourzutschky and Yakov Konoval
found a position potentially leading to a 526 moves mate
Tim Krabbé's comment on this KQN/KRBN
[youtube version].
This figure has to be confirmed, as databases are not complete, and the distance to mate for this position
is only upper bounds via a capture and then a reduction to a smaller size problem.
( Lutz Neweklowsky created a 530 moves mate problem based on this position).
A 202 moves mate position was actually reached in game in 1976. A legal 270 moves mate position was created by
Nenad Petrović in 1969.
[local copy,
youtube version ]
There is another checkmate problem in 292 moves by Bláthy, I will comment on it later because the solutions I saw online are buggy.
If you have any information improving/completing all those figures, please email me. I also suggest to have a look on R.
Stanley's slides for a talk on extremal chess problems. Another nice (short) famous checkmate problem
: the Saavedra position. Questions/comments on this page:
Cyril.Banderier at lipn.univparis13.fr
10 
Created with PGNtoJS