The Bureau of State Parks and Recreation division of Department of Conservation and Recreation (Massachusetts) (DCR) is responsible for the maintenance and management of over 450,000 acres (1,820 sq km) of privately and state-owned forests and parks, nearly 10% of the Commonwealth's total land mass. Within the lands managed by the Bureau of State Parks and Recreation are some 29 campgrounds, over 2,000 miles (3,200 km) of trails, 87 beaches, 37 swimming, wading, and spray pools, 62 playgrounds, 55 ballfields, and 145 miles (233 km) of paved bike and rail trails.