Delirium Wilderness is a 11,870-acre (48.0 km2) wilderness area in Chippewa County, within the Hiawatha National Forest in the U.S. state of Michigan.The Wilderness is forested, flat, and rolling, often characterized as a swamp, with elevations ranging from 590 to 890 feet (180 to 270 m). Sculpted by glaciers and an ancient glacial lake, it now contains the 80-acre (32 ha) Sylvester Pond and the 6-acre (2 ha) Delirium Pond, as well as the headwaters of the Pine and Waiska Rivers.