The California Department of Parks and Recreation, more commonly known as California State Parks, manages the California state parks system. The system administers 279 separate park units on 1.4 million acres (570,000 hectares), with over 280 miles (450 km) of coastline; 625 miles (1,000 km) of lake and river frontage; nearly 15,000 campsites; and 3,000 miles (4,800 km) of hiking, biking, and equestrian trails. Headquartered in Sacramento, park administration is divided into 21 districts. The California State Parks system is the largest state park system in the United States.