Interstate 81 in Tennessee

Interstate 81
I-81 highlighted in red
Route information
Maintained by TDOT
Length	75.66 mi[1] (121.76 km)
Existed	August 14, 1957[2]–present
History	Completed August 27, 1975[3]
NHS	Entire route
Major junctions
South end	I-40 near Dandridge
Major intersections	US 25E near Morristown US 11E near Greeneville I-26 / US 23 near Kingsport US 11W in Bristol
North end	I-81 at the Virginia state line in Bristol
Location
Country	United States
State	Tennessee
Counties	Jefferson, Hamblen, Greene, Washington, Sullivan
Highway system
Interstate Highway System Main Auxiliary Suffixed Business Future Tennessee State Routes Interstate US State
← SR 80 → SR 81

Interstate 81 (I-81) is part of the Interstate Highway System that runs 855.02 miles (1,376.02 km) northward from Dandridge, Tennessee, to the Thousand Islands Bridge at the Canadian border near Fishers Landing, New York. In Tennessee, I-81 serves the northeastern part of the state, running 75.66 miles (121.76 km) from its southern terminus with I-40 in Dandridge to the Virginia state line in Bristol. The route serves the Tri-Cities region of the state and the eastern parts of the Knoxville metropolitan area, terminating about 35 miles (56 km) east of Knoxville. I-81 bypasses most cities that it serves, instead providing access via interchanges with state and federal routes. It remains in the Ridge-and-Valley topographic region of the Appalachian Mountains for its entire length in Tennessee, and runs in a northeast to southwest direction.

I-81 roughly follows the corridors of U.S. Routes 11E and 11W in Tennessee, but unlike many stretches of Interstate Highways, does not closely parallel any U.S. Numbered Highway until it reaches Bristol. The first parts of I-81 in the state were constructed in the early 1960s, with additional progress made on the Interstate throughout that decade. However, most of the route was constructed later than the other Interstate Highways initially allocated to Tennessee, and did not open until after 1970. The last stretch of I-81 in Tennessee, which was more than half of the entire route in the state, was completed in 1975. From 1985 to 2007, the Interstate had one auxiliary route, I-181, which was renumbered as part of I-26.