Castling

is a move in the game of chess involving a player's king and either of the player's original rooks. It is the only move in chess in which a player moves two pieces in the same move, and it is the only move aside from the knight's move where a piece can be said to "jump over" another

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  The Dutch chess player / writer Tim Krabbé ever devised a special castling: when a pawn is promoted to the e-line to a tower, it could be a "lengthy castling. With that tower, after all, do not turn out to be done. However, modern rules do not allow it, because it says that the king must move aside when castling.