A recreation area is a type of protected area designated in some jurisdictions. In the United States, National Recreation Areas are administered by several different agencies. They typically do not meet the strict guidelines to become national parks. In U.S. state park systems, recreation areas may also fail to meet some criteria to be designated state parks, such as having a large number of non-contiguous properties. Size is not necessarily a defining criterion. For instance, in Michigan, the largest state recreation area, Waterloo Recreation Area is 20,500-acre (83 km2) while the smallest state park is the 31-acre (0.13 km2) Tri-Centennial State Park and Harbor.