The medium sandstone boulder offers graduated challenges for children ages 5-12 as they ascend to a height of 5 feet. The molded detail gives the boulder a truly organic feel that will complement naturalized play spaces. Consider combining large and medium playground boulders to create an arch, adding even more rock climbing and active play opportunities. The NatureROCKS sandstone boulders are artfully designed from real rock outcroppings and hand painted to look and feel like sandstone. Each playground boulder is constructed of durable, weatherproof glass fiber reinforced concrete (GFRC). All boulders also feature built-in forklift channels to easily facilitate delivery and placement.