Fortress Solitaire is a solitaire card game where the goal is to arrange a 52 card deck into 4 piles (foundations) of cards arranged in order and by suit. In fortress solitaire, the cards are initially dealt into 10 piles, 8 piles of 5 and 2 piles of 6. Only the top card in these piles may be moved between the piles or to the foundations. Cards can be built up or down in the piles, but only up in the foundations.