I-77 begins as a six-lane highway at I-26 in the far southeastern part of the Columbia metropolitan area. The Columbia skyline is visible from this interchange. In the Columbia area, I-77 offers easy access to Fort Jackson before meeting I-20 in the northeastern part of the city. This segment of I-77, combined with I-20 and I-26, form a beltway around Columbia, though it is not officially designated as such. In the Columbia area, the control city for northbound traffic is Charlotte, North Carolina, while the control city for southbound traffic is Charleston, South Carolina.
After leaving the northern Columbia suburb of Blythewood, I-77 narrows to four lanes until Rock Hill. From Exit 75 near Rock Hill to the North Carolina state line, the highway widens to eight lanes following a recent widening project. The final exit in South Carolina, Exit 90, takes motorists to Carowinds, an amusement park that was built along the North and South Carolina state line.
Interstate 77 through North Carolina begins at the South Carolina state line at Pineville where the Carowinds theme park is visible. It then travels south of Charlotte and through downtown before entering piedmont North Carolina. In Charlotte it intersects Interstate 85 as well as intersecting each of the loops of Interstate 485 and Interstate 277 (twice). North of Charlotte, it skirts Lake Norman, while passing through Huntersville, Cornelius, Davidson and Mooresville. Forty miles north of Interstate 85, at Statesville it intersects Interstate 40. The final intersection is with a discontinuous section of Interstate 74 near Mount Airy within sight of the Southern Blue Ridge that Interstate 77 will climb shortly after leaving the state of North Carolina.
Interstate 77 in Charlotte, North Carolina is also known as the "Bill Lee Freeway"; this designation stretches from Exit 6 (South Tryon Street/Woodlawn Road) in Charlotte to Exit 33 (US 21 North), near Mooresville. A 6-mile (9.6-km) portion south of the city is called the "General Younts Expressway". When I-77 crosses over I-85 (which runs in an east-west direction through the interchange), the northbound lanes are to the west of the southbound lanes. Likewise, southbound I-77 is to the east of northbound I-77.
Interstate 77 through Virginia passes through two tunnels. The Big Walker Mountain Tunnel and the East River Mountain Tunnel provide quick interstate access with minimal environmental disruption. For eight miles, Interstate 77 overlaps with Interstate 81 near Wytheville. This is a wrong-way concurrency, where 2 roads run concurrent with each other but are designated in opposite directions.
The highway passes through "Virginia's Technology Corridor" despite its very rural and isolated settings. Outside of Wytheville, there is little in the way of development.
Interstate 77 enters from Virginia through the East River Mountain Tunnel. At milepost 9, Interstate 77 becomes co-signed with the West Virginia Turnpike for the next 88 miles (142 km), a toll road between Princeton and Charleston. It is concurrent with Interstate 64 to Charleston at Beckley. The speed limit is 70 MPH for most of the length, with a 60 MPH limit for the section between Marmet and the second toll plaza.
It enters Charleston via the Yeager Bridge and passes by the state capitol complex before splitting off at a four-level junction with Interstate 64 in the downtown. Two miles north of the city center, it junctions with Interstate 79 before proceeding northward towards Ripley and Parkersburg. It leaves the state at Williamstown for Ohio.
North of Charleston, Interstate 77 is known as the "Korean War Veterans Memorial Highway". Within the city limits of Charleston, it is labeled as the "Nurse Veterans Memorial Highway" although not signed or mentioned as such. The toll-free section south of Princeton to Virginia is known as the "Hugh Ike Shott Memorial Highway" although no signage exists to identify it as such. In practice, none of these terms are used by the general public.
Entering from West Virginia at Marietta, Interstate 77 passes through rolling Appalachian terrain.
The interchange with I-70 at Cambridge is (or at least at one time was) thought to be the largest interchange in the world, covering over 300 acres of land.
Other major interstate highways I-77 connects with in Ohio are I-76, I-80 (Ohio Turnpike), and I-90. The interchange with the Ohio Turnpike was completed in the early 2000s, providing direct access-previously traffic had to exit at Ohio State Route 21 to get to the Turnpike.
Interstate 77 is also known as the "Vietnam Veterans Memorial Highway" in Ohio.