Horse Pens 40 is a privately owned outdoor nature park located in St. Clair County near Steele, Alabama. The park is situated atop Alabama's third-highest mountain, Chandler Mountain, in the foothills of The Appalachian Mountains. The park is known among the rock climbing community as a premier bouldering site in the American Southeast. The site is also home to a "Bluegrass Park" where it hosts festivals showcasing the genre several time per year. The biggest of these festivals occurs on the Fourth of July.