Former Interstate 181

Interstate 181 (I-181) was established in December 1985 as an interstate designation of US-23, which was already built to interstate standards in the 1970s. I-181 traversed from US-321/SR-67, in Johnson City, to US-11W/SR-1, in Kingsport, totaling 23.85 miles (38.38 km). US-23 continued on both directions as interstate grade to the Virginia line, to the north, and 15 miles (24 km) south to Erwin; by 1992, US-23 was upgraded to interstate grade south to Sam's Gap, at the North Carolina line. All exit numbers were based on US-23 mileage. On August 5, 2003, after completion of a 9-mile (14 km) section completed in North Carolina, I-26 was extended west into Tennessee, replacing I-181 from Johnson City to I-81; north of I-81, I-181 continued into Kingsport. The American Association of State Highway and Transportation Officials (AASHTO) initially ruled against an extension of Interstate 26 (as the number) along the remainder of I-181 to Kingsport, since that would give a main route Interstate Highway (I-26) a so-called "stub end," not connecting to any other Interstate highway, to an international border, or to a seacoast. The numerical extension was in 2005 enacted by the effect of the Safe, Accountable, Flexible, Efficient Transportation Equity Act: A Legacy for Users, signed into law on August 10, 2005. In March 2007, I-181 was officially decommissioned, as all signs and exit numbers were changed-over to I-26's designation.