Hartley Nature Center is an independent, non-profit, environmental education organization located in the beautiful 660-acre Hartley Park in Duluth, Minnesota. Hartley Nature Center's mission is to provide opportunities for understanding, appreciation, and stewardship of the natural world. Address: 3001 Woodland Ave. Duluth, MN 55803 Hours: Monday-Friday, 9-5, Sat, 10-5, Sun, 12-5 Phone: (218)-724-6735 Email: info@hartleynature.org