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Chapter 04 · Beginner · 4 min

Castling

Castling tucks the king away and wakes up a rook. It is the only move where two pieces move together, because chess likes one little exception.

Explanation

Castling is a special move to secure the king and activate the rook.

During castling, the king moves two squares toward a rook, then the rook moves to the other side of the king. This is the only move where two pieces move at the same time. Small castling on the king side, large castling on the queen side.

Castling is allowed only if the king and rook have never moved, if the squares between them are free, if the king is not in check, and if the king does not cross an attacked square. The rook can be attacked: what counts are the king's squares. Yes, it's a small list, but it quickly becomes automatic.

Petit castling: king towards g1 or g8.
Grand castling: king towards c1 or c8.
The king must not pass through an attacked square.

To remember

Castling moves the king and the rook. It is used to shelter the king and activate the rook.

Classic error

Attempt to castle while in check, through an attacked square, or with pieces between the king and the rook.

Player Tip

Castling early when possible. A king in the center for too long invites trouble.