Four Holes Swamp is a small blackwater river

Blackwater river

A blackwater river is a river with a deep, slow-moving channel that flows through forested swamps and wetlands. As vegetation decays in the water, tannins are leached out, resulting in transparent, acidic water that is darkly stained, resembling tea or coffee. Most major blackwater rivers are in...

 that is a tributary to the Edisto River

Edisto River

The Edisto River is the longest completely undammed / unleveed blackwater river in North America, flowing 206 meandering miles from its sources in Saluda and Edgefield counties, to its Atlantic Ocean mouth at Edisto Beach, SC...

 in South Carolina

South Carolina

South Carolina is a state in the Deep South of the United States that borders Georgia to the south, North Carolina to the north, and the Atlantic Ocean to the east. Originally part of the Province of Carolina, the Province of South Carolina was one of the 13 colonies that declared independence...

. The swamp rises in Calhoun County

Calhoun County, South Carolina

Calhoun County is a county located in the U.S. state of South Carolina. In 2000, its population was 15,185; a 2005 Census Bureau estimate placed the population at 15,100. It is named for John C. Calhoun, the former U.S. Vice-President, Senator, Representative and cabinet member from South...

 and flows 62 miles (100 km) to the confluence, in an unusual braided pattern; it has no well-defined channel, but multiple channels that start and disappear, yet maintain a flow.

The swamp is the home of the Francis Beidler Forest

Francis Beidler Forest

The Francis Beidler Forest is an Audubon wildlife sanctuary in Four Holes Swamp, a blackwater creek system in South Carolina. It consists of over 16,000 acres of mainly bald cypress/tupelo gum swamp with approximately of old-growth forest. It has an environmental education center and a ...

, a 16000 acres (64.7 km²) nature preserve of virgin cypress

Taxodium

Taxodium is a genus of one to three species of extremely flood-tolerant conifers in the cypress family, Cupressaceae...

 and tupelo

Tupelo

The tupelo , black gum, or pepperidge tree, genus Nyssa , is a small genus of about 9 to 11 species of trees with alternate, simple leaves...

 forest owned and operated by the Audubon Society. Some of the trees are over 1000 years in age, and the forest is the home of a number of rare or endangered species

Endangered species

An endangered species is a population of organisms which is at risk of becoming extinct because it is either few in numbers, or threatened by changing environmental or predation parameters...

.