[5] Located along the L'Anguille River in the Arkansas Delta just north of the St. Francis National Forest, the community was known as "Walnut Ridge" until 1852 when it became known as "Marianna".

[citation needed] Marianna hosted minor league baseball.

[10] Marianna is located in the center of the county at the northwest tip of St. Francis National Forest.

U.S. Route 79 passes through the north and west sides of the town, leading northeast 58 miles (93 km) to Memphis, Tennessee, and southwest 90 miles (140 km) to Pine Bluff.

[11] According to the United States Census Bureau, the town has a total area of 3.61 square miles (9.36 km2), all land.

[13] As of the 2020 United States Census, there were 3,575 people, 1,545 households, and 831 families residing in the city.

The fault is close to, but appears to be separate from, the nearby New Madrid Seismic Zone.

[19] At the WWTP, two lagoons are used to treats wastewater and discharge treated effluent to the L'Anguille River in accordance with the town's NPDES permit administered by the Arkansas Department of Environmental Quality.