Mississippi Highway 30 is a state highway that runs across the North Central Hills of the Appalachian Mountains in northeast Mississippi. It travels east–west for 91.1 miles (146.6 km) from MS 7 at Oxford, Mississippi to the Natchez Trace Parkway in Mingo near the Alabama state line.

Mississippi Highway 178 (MS 178), or simply "Old 78", is a 119.1-mile-long (191.7 km) east-west state highway across the northern portion of the state of Mississippi. It is the former alignment of U.S. Route 78 (US 78), used from the 1940s until the 1990s. With the exception of a break at the Tennessee-Tombigbee Waterway in Fulton, MS 178 is a complete route from Memphis, Tennessee, to the Alabama state line.