@greenpawn34 saidb1 is OK. The King stops short of it.
Hi Ichmude,
If during castling the King passes over a square that is being attacked, in the case
of Queen side castling, that is the squares d1, c1 and b1. then it is not allowed.
@BigDoggProblem
I know, I was away with the fairies there. Stopped what I was doing about 30
minutes ago and remembered what I had said. 😀
Expecting someone to come back and say:
"Hey: when I castle Queen side my King stops on c1 , what is wrong?"
@greenpawn34
Reminds me of some kids I watched playing when I first started to try to learn to play chess. One kid castles with his queen to b1 and rook to c1. He called it quastling and believed it was a legal move.
Yuri Averbakh vs. Cecil John Seddon Purdy
Australian Championship |Adelaide, Australia | Round 4 |1960
According to GM Larry Evans and his book "Chess Catechism":
"Black castled queenside. Averbakh pointed out that the rook passed
over a square controlled by White and thought it was illegal. Purdy
proved that the castling was legal since this applies only to the king,
to which Averbakh replied: "Only the king? Not the rook?"
http://www.chessgames.com/perl/chessgame?gid=1329062&kpage=1
@wolfgang59 saidI remember reading about Korchnoi questioning the rules about queenside castling in a game once as well, so the rule must be a little fuzzier than one would believe.
Yuri Averbakh vs. Cecil John Seddon Purdy
Australian Championship |Adelaide, Australia | Round 4 |1960
According to GM Larry Evans and his book "Chess Catechism":
"Black castled queenside. Averbakh pointed out that the rook passed
over a square controlled by White and thought it was illegal. Purdy
proved that the castling was legal since this applies onl ...[text shortened]... "Only the king? Not the rook?"
http://www.chessgames.com/perl/chessgame?gid=1329062&kpage=1
I've been R&Ding chess variant support - castling support for some variants can get quite a bit more complex. For example : double chess, a 16*8 board with 4 rooks each.
If this ever sees the light of day, future me will surely regret it...I can only imagine the number of support questions regarding castling.
EDIT:
Let me try this again. I did not do a good job of proof-reading my previous post.
The only restriction on the rook that is castling is that it cannot have already been moved.
The king cannot have already moved, and he also cannot castle while in check and he cannot move across or end up on a square that is under attack by the opponent.
And lastly, all squares between the king and the rook that is involved in castling must be empty.
I believe those are all of the rules for castling.
@russ saidBe sure to include quastling.
I've been R&Ding chess variant support - castling support for some variants can get quite a bit more complex. For example : double chess, a 16*8 board with 4 rooks each.
If this ever sees the light of day, future me will surely regret it...I can only imagine the number of support questions regarding castling.