Expert: Tony D'Aloisio - 11/27/2009

Question
Can you switch the King with the castle?

Answer
You're probably thinking of castling.  Here's how it works:

To castle on the king's side (ie, to your right if you're White; you have to reverse this if you're Black, so you would then be moving to your left to castle king's side), move your king two squares to the right.  It should now be on the square next to your rook (it's a good idea btw to get in the habit of calling "castles" rooks; one reason for this is so as not to confuse the piece with the castling move).  Now you move the rook from the square it's on to the one immediately to the left of the king.  All of this counts as one move.

You can also castle on the queen's side.  Move the (White) king two squares to the left (again, reverse the direction if you're playing Black).  There should now be a single square between your king and the rook on that side.  Then you move the rook to the square immediately to the right of the king.

There are several conditions that have to apply in order for castling to be legal.  These are:

1) neither the king nor rook in question can have made a move earlier;

2) there can be no pieces (of either color) on the squares between the king and rook;

3) the king cannot castle out of, through, or into check (however, an enemy piece can attack the rook in question, or--in the case of queenside castling--the square right next to it; as long as the king is not so attacked, the move will be legal).

If this all sounds a bit complicated, bear in mind that Viktor Korchnoi--one of the best players ever--once had to have that 3rd point explained to him in the middle of a world championship match game!  So even the greats have been known to have a bit of trouble with this.