I-77 highlighted in red
|Maintained by SCDOT|
|Length||91.2 mi (146.8 km)|
|South end||in Cayce|
|North end||/ at the NC state line|
|Counties||Lexington, Richland, Fairfield, Chester, York|
Interstate 77 (I-77) is a south-north Interstate highway, extending 91.2 miles (146.8 km) in the state of South Carolina, extending from the national southern terminus at an interchange with I-26 near Columbia, north to the North Carolina state line near Rock Hill and Charlotte, NC.
I-77 is designated a Blue Star Memorial Highway for its entire length in South Carolina. The highway also has a trio of designations in the Columbia area. I-77 is named the Veterans Memorial Freeway from I-26 to the Congaree River, the William Earle Berne Beltway from the river to I-20, and the Charles F. Bolden Freeway from I-20 to the Richland–Fairfield county line.
I-77 begins at a semi-directional T interchange with I-26 in the city of Cayce. The interchange includes a pair of ramps between I-77 and Charleston Highway, which carries US 21, US 176, and US 321. I-77 heads east as a six-lane freeway that crosses over CSX's Columbia Subdivision and has a diamond interchange with SC 35 (12th Street Extension). The Interstate crosses the Lexington–Richland county line on its bridge across the Congaree River. I-77 has a partial cloverleaf interchange with SC 48 (Bluff Road), crosses Gills Creek, and meets SC 768 (Shop Road) at a cloverleaf interchange.
I-77 enters the city of Columbia at its crossings of Norfolk Southern Railway's SC Line and CSX's Eastover Subdivision. The freeway has a connected pair of elongated partial cloverleaf interchanges with US 76 and US 378 (Garners Ferry Road) and SC 262 (Leesburg Road). The Interstate passes through an S-curve, within which the highway has a diamond interchange with SC 760 (Fort Jackson Boulevard), then follows the western edge of Fort Jackson. I-77 has a diamond interchange with Forest Drive and Strom Thurmond Boulevard and a partial interchange with Decker Boulevard as it veers northeast. The freeway veers north and leaves the military base and the city of Columbia at its partial cloverleaf interchange with SC 12 (Percival Road).
I-77 passes through the unincorporated suburb of Woodfield and meets I-20 at an interchange with a pair of flyover ramps; there is no access from eastbound I-20 to northbound I-77. The Interstate continues as a six-lane freeway across Windsor Lake into the suburb of Dentsville. The freeway passes under CSX's Hamlet Subdivision and has a partial cloverleaf interchange with US 1 (Two Notch Road). I-77 has a partial interchange with SC 277; the interchange includes ramps from southbound I-77 to SC 277 and from SC 277 to northbound I-77. Intertwined with the SC 277 interchange is a partial cloverleaf interchange with SC 555 (Farrow Road); within the interchange, the freeway passes under Norfolk Southern's R-Line. I-77 widens to a eight-lane freeway while it crossed at the interchange with SC 555
As it leaves the Columbia area, I-77 has a diamond interchange with Killian Road, I-77 downgraded to a six-lane freeway while it's crossed Killian Road. I-77 continues and crosses US 21 with a partial cloverleaf interchange, (Wilson Boulevard). North of its diamond interchange with Blythewood Road in Blythewood, the highway enters Fairfield County. I-77 meets SC 34 west of the town of Ridgeway and passes under the NS R-Line. The freeway passes to the east of Winnsboro, which is accessed via SC 34 or the next interchange with Road 41. I-77 has junction with Road 20 and SC 200 near Mitford before entering Chester County. The freeway has an interchange with SC 97 (Great Falls Road), which connects the county seat of Chester to the west with the town of Great Falls to the east. Great Falls is where the Piedmont-based Catawba River reaches the Fall Line and becomes the Wateree River of the Atlantic Coastal Plain.
At Richburg, I-77 has interchanges with Road 56 and SC 9 (Lancaster Highway) just before the freeway enters York County. The highway has interchanges with SC 901 (Mount Holly Road) and Porter Road on the southeast side of Rock Hill. I-77 expands to eight lanes at its partial cloverleaf interchange with US 21 and SC 5 (Anderson Road) and enters the city of Rock Hill. The freeway has a diamond interchange with SC 122 (Dave Lyle Boulevard) west of the Rock Hill Galleria. North of its underpass of the Columbia District rail line, I-77 has a pair of connected partial cloverleaf interchanges with US 21 (Cherry Road) and SC 161 (Celanese Road). The Interstate then leaves the city of Rock Hall by crossing the Catawba River.
I-77 has interchanges with Sutton Road and SC 160 (Steele Creek Road) as it passes along the western edge of Fort Mill. North of Fort Mill, the Interstate has a diamond interchange with SC 460 (Gold Hill Road). SC 460 provides access to Knights Stadium, home of the Charlotte Knights of minor league baseball. I-77's final interchange in South Carolina is with Carowinds Boulevard, which provides access to the Carowinds theme park immediately to the west on the South Carolina–North Carolina state line. At the partial cloverleaf interchange, US 21 begins to run concurrently with I-77; the two highways cross the state line together into the city of Charlotte.
Interstate 77 was originally planned to terminate at Interstate 85 in Charlotte, North Carolina; in 1969, U.S. Congress passed an amendment to the Interstate Highway act to extend the route south along US 21 into South Carolina, where it would continue south terminating at I-20, near Columbia, South Carolina. The proposed routing started appearing around 1971, going south from a stub freeway section of US 21, from the North Carolina state line, to US 21/SC 5, near Rock Hill; by 1975, the entire proposed route on all state and federal maps.
The first section completed and designated as I-77 around in 1975, from US 21 (exit 90) to US 21/SC 161 (exit 82). In 1976, it was extended south to US 21/SC 5 (exit 77). In 1979, I-77 was completed and designated on a southern section from SC 277 (exit 18) to US 21 (exit 24). By 1981, the southern section extended north to SC 34 (exit 34), near Ridgeway; the northern section was also extended south to SC 9 (exit 65). By the end of 1982, the two sections merged, from SC 277 to the North Carolina state line.
In 1987, I-77 was extended south to SC 12 (exit 15), which finally accomplished its original objective of connecting with I-20. However, one year prior, I-77's southern terminus was changed to end at I-26, in Cayce; this created the establishment of Temporary I-77 around Columbia. On June 15, 1995, I-77 was extended east around Columbia on both new primary routing and existing routing, replacing unsigned I-326 and Temporary SC 478. Temporary I-77 was also decommissioned that same year. In the mid-2000s, I-77 was widened to eight-lanes from US 21/SC 5 to the North Carolina state line.
In 1976, I-77 received exit numbers along its routing; which were all renumbered in 1987-1988.
|Location||Cayce-Columbia, South Carolina|
|Length||20.0 mi (32.2 km)|
Temporary Interstate 77 (Temp I-77) was a temporary designation that directed travelers from exit 116 on I-26, in Cayce, that went clockwise around Columbia, also overlapping I-20 and then SC 277, before connecting with mainline I-77, at exit 18. The 20.0-mile (32.2 km) routing affixed temporary shields from 1986 to 1995, when I-77 was extended south to its current southern terminus.
Interstate 326 (I-326) was an unsigned designation of the six-lane limited access highway that traversed from Interstate 26, in Cayce, to SC 48, in Columbia. Established in 1976, the freeway was not completed until August 22, 1986; however it was only labeled as "To SC 48." Around 1990, when the freeway was extended further north, it took the name "Temp SC 478." The unsigned designation remained unchanged until June 15, 1995, when it was renumbered as part of I-77.
|Location||Cayce-Columbia, South Carolina|
|Length||8.5 mi (13.7 km)|
Temporary South Carolina Highway 478 (Temp SC 478) was the designation of the six-lane limited access highway that traversed from Interstate 26, in Cayce, to US 76/US 378, in Columbia. Appearing in 1989, it overlapped the unsigned section of I-326 and then on new freeway, that opened around 1990, from SC 48 to US 76/US 378. On June 15, 1995, it was renumbered as part of I-77. Throughout its existence, it was signed as only temporary.
|County||Location||mi||km||Old exit||New exit||Destinations||Notes|
|Lexington||Cayce||0.0||0.0||- Charleston, Spartanburg||I-77 ends|
|1.0||1.6||1||/ / - Gaston, Swansea, Columbia||Southbound exit and northbound entrance|
|1.8||2.9||2||north - Cayce, West Columbia|
|Richland||Columbia||5.4||8.7||5||(Bluff Road) - Gadsden|
|6.5||10.5||6||(Shop Road)||Northbound signed exits 6A (east) and 6B (west)|
|8.6||13.8||9A||/ (Garners Ferry Road) - Sumter||Southbound signed as exits 9A (east) and 9B (west)|
|12.4||20.0||12||Forest Drive, Strom Thurmond Boulevard – Fort Jackson|
|13.5||21.7||13||Decker Boulevard||Northbound exit and southbound entrance|
|15.0||24.1||15||(Percival Road)||Northbound signed as exits 15A (east) and 15B (west)|
|16.0||25.7||1||16||- Florence, Augusta||Signed as exits 16A (east) and 16B (west)|
|17.5||28.2||2||17||(Two Notch Road)|
|18.8||30.3||3||18||south to west - Columbia, Augusta|
|Blythewood||24.3||39.1||8||24||(Wilson Boulevard) - Blythewood|
|27.4||44.1||11||27||Blythewood Road – Blythewood|
|Fairfield||||32.4||52.1||32||Peach Road – Ridgeway|
|||34.1||54.9||18||34||- Ridgeway, Winnsboro, Camden|
|||41.0||66.0||25||41||Road 41 – Winnsboro|
|||45.7||73.5||30||46||Road 20 – White Oak|
|||48.2||77.6||32||48||- Great Falls, Winnsboro|
|Chester||||55.3||89.0||39||55||- Great Falls, Chester|
|||62.5||100.6||46||62||Road 56 – Fort Lawn, Richburg|
|||64.7||104.1||49||65||- Chester, Lancaster, Fort Lawn|
|York||Rock Hill||72.9||117.3||57||73||- Rock Hill, York|
|77.2||124.2||61||77||/ - Rock Hill, Lancaster|
|79.1||127.3||63||79||(Dave Lyle Boulevard) - Downtown Rock Hill|
|81.7||131.5||66||82||/ - Fort Mill, Rock Hill, York||Signed as exits 82A (north), 82B (south), and 82C (SC 161)|
|Fort Mill||83.4||134.2||67||83||Sutton Road|
|85.6||137.8||69||85||- Tega Cay, Fort Mill|
|||87.9||141.5||72||88||(Gold Hill Road) - Tega Cay||To Knights Stadium|
|||90.4||145.5||74||90||south / Carowinds Boulevard - Fort Mill||South end of US 21 overlap; to Carowinds|
|||91.2||146.8||north / north - Charlotte||Continuation into North Carolina|
|1.000 mi = 1.609 km; 1.000 km = 0.621 mi|