Castle Solitaire is a modified version of Beleaguered Castle Solitaire with rules that make it more likely a player will win the game. In Castle Solitaire, like Beleaguered Castle Solitaire the game begins with the player dealing the four aces into the center of the game as the foundations followed by the remaining 48 cards being dealt into 8 piles, one to the right and one to the left of each of the foundations.
Unlike in Beleaguered Castle Solitaire, Castle Solitaire allows the players to build the piles up or down regardless of suit. In Beleaguered Castle Solitaire the player may only build the piles down. This means a skilled player is much more likely to win.