Castling

Castling is the only move in chess where you move two pieces at once. The idea is very practical: get the king out of the center, where it’s exposed, and activate the rook in a single move. Not a bad deal, right?

What is castling

When you castle, the king moves two squares toward one of your rooks, and that rook jumps to the other side of the king. There are two versions:

• Kingside castling: the king moves toward the kingside.
• Queenside castling: the king moves toward the queenside.

Both serve the same purpose: improving king safety and connecting your pieces better. Once you master it, you’ll see that most openings partly revolve around preparing it as soon as possible.

Practice kingside castling

Practice queenside castling

When you can’t do it

Castling fails if any of these conditions is broken:

1. The king has already moved before.
2. The chosen rook has already moved before.
3. There are pieces between the king and the rook.
4. The king is in check.
5. The king would cross an attacked square.
6. The king would land on an attacked square.

Here’s the key: the king can never castle through danger. If the opponent controls any of the squares it has to pass through, castling is forbidden that turn. No shortcuts.

When it’s worth castling

Here’s the practical advice. In most games you want to castle early, as soon as you’ve developed the pieces on that side. A king left in the center of the board is an easy target once files and diagonals open up. On the other hand, an already-activated rook joins the game much sooner.

What if the opponent hasn’t castled yet? Then opening the center can be a weapon. But that’s already intermediate strategy; for now, focus on castling before move ten whenever you can.

If you want to continue with the basic rules, checkmate, piece movement, the king, and the complete rules of chess will also come in handy.