June 19, 2018 Mark F Hike, Hiking, CT, US Old Furnace State Park, Killingly, CT June 19, 2018 Mark F Hike, Hiking, CT, US Old Furnace State Park is located in Killingly near Rhode Island. This is a great park for hiking, biking, and fishing. Exploring new areas is always fun, even if you get lost on the trails. Check out the blog to make sure you stay on the trails!