D-Day at Iwo Jima is a solitaire game simulating the amphibious invasion of Iwo Jima. The five-week battle was some of the bloodiest fighting in the Pacific. In one of the costliest intelligence failures of the war, the planners had completely misjudged the situation that would face the Marines. The beaches had been described as excellent and the advance inland was expected to be easy. Instead, the Marines were faced with 15-foot-high slopes of soft black volcanic ash that brought the normally rapidly moving Marines down to a slow plod. In addition, the lack of a vigorous response led the Marines to believe that the bombardment had completely suppressed the defenses. However, Gen. Kuribayashi was far from beaten. Understanding that his forces were insufficient to defeat the massive American invasion force, he had decided to defend the island in-depth.