sentences:  There are many bogs throughout the park that are surrounded by dense vegetation, giving the park a jungle-like atmosphere.The park was constructed by Civilian Conservation Corps (CCC) Companies 873 and 886 between 1934 and 1937.The CCC built Park Road 11, a low water crossing on the San Marcos River, a water tower/storage building, refectory, and residence (currently the park headquarters), barbeque pits, picnic seating, rock pool and retention dams, rock table, culverts, concrete picnic tables, and two sets of entrance portals.