The Santa Fe River is a 75-mile (121 km) river in northern Florida. The watershed of the river is approximately 1,380 square miles (3,574 km²) and spreads across southern Columbia, southern Suwannee, western Bradford, far southern Baker, Union, northern and eastern Gilchrist, and northern Alachua counties. The headwaters of the river are Lake Santa Fe, near Keystone Heights. The Santa Fe River is usually a slow-flowing river.