At one time, the rumble of freight cars reverberated through the narrow tunnel. Wooden trestles, with their system of slanted supports and horizontal cross pieces, spanned numerous bluffs and creeks. Passengers in Pullman cars clocked the miles with these and other landmarks as they traveled one of southern Illinois' most scenic routes.Today, the railroad is gone. The route, known as Tunnel Hill State Trail, remains.Tunnel Hill State Trail stretches for 45 miles from Harrisburg to Karnak. The trail continues on a trails spur for 2.5 miles from Karnak to Cache River State Natural Area - Henry Barkhausen Wetlands Center on the old Chicago and Eastern Illinois railroad bed.The 9.3-mile section between Tunnel Hill and Vienna crosses trails already known to outdoor recreationists: the River-to-River Trails, which extends from the Mississippi to the Ohio River; the unmarked American Discovery Trails, which in southern Illinois follows back roads and some of the River-to-River Trail; the U.S. 76 Bicycle Route, a part of the TransAmerica Bike Route; and the Trail of Tears, the primary route the Cherokee Indian tribe took in the winter of 1838-39 during their forced move from the Great Smokies to Oklahoma.