CHECKCHESS RoundBoard (1991)

CHECKCHESS RoundBoard contains standard sets of chessmen and checkers, but as the name implies the real star is the game board. The circular board consists of eight rings of eight spaces each. Each ring corresponds to one of the eight ranks on a standard chessboard, and each radially-aligned group of spaces corresponds to a file. (They're even labeled 1-8 from outside to inside and a-h counterclockwise, and the rulebook calls them "squares" despite their curved shape.)

The pieces are set up with one player on the outside of the circle facing in and the other in the center facing out (but otherwise exactly as in ordinary chess or checkers) and the rules of those games are unchanged except that file "a" and file "h" are considered adjacent for the purposes of movement. This is equivalent to the variant in which pieces are allowed to move off the right side of a square chess board onto the left and vice versa, but on the round board all legally-adjacent spaces are also physically adjacent.

From the designer's notes included with the game:

"An engineer by profession, I have always had a fascination with the game of chess. As a member of my high school chess team, I played hooky from school to strengthen my game.

"In the 1960's the concept of a round board interested me as a novelty. However, some 25 years later I made a serious study of that novelty and concluded that the round board is a major evolutionary advancement in the games of chess and checkers. I hope you share my belief and enjoy your games on CHECKCHESS RoundBoard(TM)."