Interstate 26 (Tennessee)
U.S. Route 23 (US 23) is a part of the U.S. Highway System that travels from Jacksonville, Florida to Mackinaw City, Michigan. In the U.S. state of Tennessee, the U.S. Highway travels 57.5 miles (92.5 km) from the North Carolina state line, at Sam's Gap, north to the Virginia state line, in Kingsport. With a predominant concurrency with Interstate 26 (I-26), US 23 is a divided four-lane freeway that follows Corridor B of the Appalachian Development Highway System and serves as a major thoroughfare in the Tri-Cities. The entire route of US 23 in Tennessee is an interstate-grade freeway.
US 23, in concurrency with I-26, enters Unicoi County at Sam's Gap (el. 3,799 ft (1,158 m)) and travels north along Stamp Ridge. Immediately after crossing the state line is a truck information station, signed "Truck Inspection," which requires all trucks to go through before continuing. The following 3 miles (4.8 km) is a 6% grade descent, accompanied with two runaway truck ramps, into the South Indian Creek valley. Between mile markers 47-48 is a scenic overlook turnoff (northbound US 23/westbound I-26 only), followed by the I-26 Erwin/Unicoi County Welcome Center, located on Clear Branch Road exit. At Temple Hill, US 19W, traveling from Burnsville, joins in concurrency.
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