Quoridor

Rules of the game

Quoridor is played on a game board of 81 square spaces (9x9). Each player is represented by a pawn which begins at the center space of one edge of the board (in a two-player game, the pawns begin opposite each other). The objective is to be the first player to move their pawn to any space on the opposite side of the gameboard from which it begins.

The distinguishing characteristic of Quoridor is its twenty walls. Walls are flat two-space-wide pieces which can be placed in the groove that runs between the spaces. Walls block the path of all pawns, which must go around them. The walls are divided equally among the players at the start of the game, and once placed, cannot be moved or removed. On a turn, a player may either move their pawn, or, if possible, place a wall.

Pawns can be moved to any space at a right angle (but not diagonally). If adjacent to another pawn, the pawn may jump over that pawn. If an adjacent pawn has a third pawn or a wall on the other side of it, the player may move to either space that is immediately adjacent (left or right) to the first pawn. Multiple pawns may not be jumped. Walls may not be jumped, including when moving laterally due to a pawn or wall being behind a jumped pawn.

Walls can be placed directly between two spaces, in any groove not already occupied by a wall. However, a wall may not be placed which cuts off the only remaining path of any pawn to the side of the board it must reach.

History

Quoridor is also based on Mirko Marchesi's earlier game Blockade which was published in the 1975. Marchesi also created another version of this game called Pinko Pallino which was published in 1995 by Epta. Pinko Pallino was only for 2 players and was played on an 11×11 gameboard with a total of 42 walls and slightly different rules.

Notation

Although there is no official notation, Lisa Glendenning's thesis proposes a reasonable notation.

The notation proposed is similar to algebraic chess notation. Each square gets a unique letter-number designation. Columns are labeled a through i from player 1's left and rows are numbered 1 through 9 from player 2's side to player 1's side. A move is recorded as the column followed by the row as in e8. Player 1's pawn starts on e9 and player 2's pawn starts on e1.

Each pawn move is defined by the new square occupied by the pawn. For example, if player 1 moves from square e9 to e8, player 1’s move is e8.

Each fence move is defined by the square directly to the northwest of the wall center from player 1's perspective, as well as an orientation designation. For example: a vertical wall between columns e and f and spanning rows 3 and 4 would be given the designation e3v.

Games are notated as they are in chess: by the move number, player 1's move, and player 2's move. For example, a game might start with each player moving their pawn towards the goal:

1. e8 e2

2. e7 e3

And then the players might add walls to lengthen the other player's path:

3. e7h e2h

and so forth.

Strategies