The 20th Maine, subtitled "The Battle for Little Round Top", is a board wargame published by Operational Studies Group (OSG) in 1979 that simulates the battle for possession of a hill called Little Round Top that anchored the left flank of the Union Army on the second day of the Battle of Gettysburg during the American Civil War. The game was republished by Avalon Hill in 1982 and titled Little Round Top.