Marion is located in Crittenden County (of which it is the county seat) just north of West Memphis, between Sunset and West Memphis along Hwy 77 on the banks of the Mississippi River, near the Tennessee boarder.

The population estimate for July 1, 1998 was 6,459, an increase of 2,054 since 1990.

Marion is part of the Memphis, Tennessee-Arkansas-Mississippi metro area.

Early settlers found a good income source in harvesting timber to sell to steamboats for fuel. The Mississippi River Levee later broke at St. Clair, the town was covered by floodwaters during late 1912 and early 1913. Today agricultural developments producing wheat, soybeans, cotton and rice have replaced the timber industry, and is also turning toward manufacturing and distribution with the opening in 1998 of Union Pacific's Intermodal RailPort.

The Mid South Community College is conveniently located within Marion.