Isalo National Park is a National Park in the Ihorombe Region of Madagascar. The park is known for its wide variety of terrain, includingsandstone formations, deep canyons, palm-lined oases, and grassland. The closest town is Ranohira, and the closest cities are Toliara andIhosy. A local guide is required for visitors entering the park, and guides and porters can be hired in Ranohira. Treks in the park can last from several hours to a week or longer.