This 0.5-mile trail parallels the swift-flowing, translucent green waters of the Vermilion River in the town of Streator, which is home to Clyde Tombaugh, the only U.S. citizen to be credited with discovering a planet (Pluto) and Clarence Mulford, author of the famous Hopalong Cassidy western series, after which the trail takes its name. Visitors can follow this trail through an urban forest of mulberry, hackberry, oak, and maple. Blue Jays, chickadees, and woodpeckers flit in and out of the riparian trees as butterflies and dragonflies frolic along the trail's sunnier stretches. The trail ends at a public canoe launch.