A question and answer column by FIDE Master Andy Lee.
Q: What are the rules for castling? And why would I want to castle, anyway?
-- Tyler, Alameda, CA
A: Castling is an incredibly important strategy in chess, particularly in the opening phase of the game. The basic rules are listed in the chesskid glossary, but here they are with some illustrative diagrams:
1) To castle, you must have no pieces between your king and your rook. Then, simply move your king two squares towards your rook, and then hop your rook over your king to the next available square.
2) You may not castle if you have moved either your king or the rook that you are castling with. The game below is a nice example of white trying to reset his king to its original square in order to fool his opponent!
3) You may not castle if your king is in check OR if your king would have to travel through check. However, you may castle if your rook is attacked:
And why would you want to castle? Castling does two important things: it brings your king to greater safety in the corner of the board where it will be less likely to be attacked. It also helps develop one of your rooks towards the center of the board. And all this in only one move! No wonder almost all games between strong chess players include castling for both sides.