<Tr> <Td> Total </Td> <Td> 854.89 </Td> <Td> 1,375.81 </Td> </Tr> <P> I - 81 begins in Tennessee at I - 40 in Dandridge, a route that connects to Knoxville to the west and Asheville to the east . I - 81 meets Interstate 26 and U.S. Route 23, which go to Kingsport and Johnson City . At mile marker 75, I - 81 leaves Tennessee and enters Virginia . </P> <P> I - 81 in Virginia is largely a rural route with brief concurrencies with I - 77 and I - 64 . The route parallels the Appalachian Mountains for much of its route through Tennessee and Virginia, serving such cities as the twin cities of Bristol, Tennessee, and Bristol, Virginia, Roanoke, Christiansburg, Lexington, Staunton, Harrisonburg, Wytheville, and Winchester . In Harrisonburg, I - 81 cuts through James Madison University . It parallels its older counterpart, U.S. Route 11, for its entire length in Virginia . </P> <P> I - 81 briefly enters the Eastern Panhandle of West Virginia for about 26 miles (42 km), serving the city of Martinsburg . The entire routing is in Berkeley County and serves the Eastern WV Regional Airport . The West Virginia segment was completed in 1966 and there have been no realignments since . West Virginia is currently widening I - 81 to six lanes from Martinsburg north to exit 23 (US 11) connecting West Virginia and Maryland . </P>

Where does the appalachian trail cross interstate 81
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