It connects the cities of Barnwell and Denmark with Orangeburg via U.S. Route 301 (US 301) and US 601.

This would be SC 70 longest length with it reaching over 42 miles (68 km) long.

Around 1958, SC 70 was re-extended east of Denmark to its current eastern terminus with US 301/US 601.

South Carolina Highway 70 Alternate (SC 70 Alt.)

was an alternate route that existed in the southeastern part of Barnwell.