Rook

The rook moves in a straight line along a horizontal row, called a rank, or a vertical column, called a file. It may travel any number of squares, but it cannot jump over another piece. A friendly piece stops it before that square; an enemy piece may be captured on that square, but the rook cannot continue beyond it.

The rook's orthogonal reach

8

7

6

5

4

3

2

a1

b

c

d

e

f

g

h

From d4, the rook extends its reach along the fourth rank and the d-file, never diagonally.

The first occupant stops the line

The white rook on d4 moves only along the fourth rank and the d-file. The friendly pawn on d6 stops the file: d5 is available, but d7 lies beyond the blocker. The black bishop on g4 is the first occupant on the rank: g4 may be captured, while h4 cannot be reached from d4.

1. From d4, the rook extends its reach along the fourth rank and the d-file, never diagonally.
2. d5 is clear, but the friendly pawn on d6 blocks the file and leaves d7 out of reach.
3. The black bishop on g4 is the first obstacle and may be captured; h4 lies beyond it.

Each player begins with two rooks in the four corners of the board. A rook is a major piece, the category containing rooks and queens, and is commonly valued at about five pawns. Its reach grows when rows or columns are clear, so a rook trapped behind its own pawns may have few useful moves even though its conventional value has not changed.

The rook also participates in castling, a special move involving a king and a rook that have not moved, provided the other legal conditions are satisfied. Outside castling, the rook keeps its ordinary movement and never jumps.