Santa Fe Swamp is a 7,046-acre wetland in north Florida, spread across Bradford and Alachua counties and lying mostly within floodplain. Along with Lake Santa Fe and Little Lake Santa Fe, it forms the headwaters of the Santa Fe River, whose waters continue to the Suwannee River and the Gulf of Mexico. About 95 percent of the swamp is floodplain, shaping its ecology and hydrology. Part of the swamp is protected within the 5,356-acre Santa Fe Swamp Wildlife and Environmental Area, donated in 1984 to the Suwannee River Water Management District. The swamp is important both as a major wetland source of the river and to protection of the broader Suwannee watershed.