Twin Shelters Trail

Twin Shelters Trail is the backbone hiking route of Pere Marquette State Park, the largest state park in Illinois at nearly 8,000 acres, traversing the dramatic limestone bluffs above the Illinois River before it merges with the Mississippi just downstream. The trail takes its name from two CCC-era stone shelters positioned on the blufftop with commanding views across the Illinois River valley — some of the finest river views available anywhere in the Midwest. The river corridor below is a major flyway for bald eagles in winter, with hundreds of eagles congregating in the open water below the lock and dam at Alton from December through February, visible from the bluff overlooks. The trail traverses the bluff edge through a forest of chinquapin oak, post oak, and shagbark hickory adapted to the thin, dry soils of the limestone ridge. The 600 feet of cumulative elevation gain reflects the constant rolling topography of the river bluffs rather than any single sustained climb. Several side spurs lead to additional overlooks and the historic Pere Marquette Lodge, a massive CCC-built stone and timber structure completed in 1941 and listed on the National Register of Historic Places. Spring turkey vulture and broad-winged hawk migration along the river bluffs is spectacular in April.