Heavy snow left northbound Interstate 81 virtually at a standstill for nearly 20 miles from Bristol to Abingdon all afternoon and evening Sunday.
Traffic stalled or moved very slowly for hours.
The backup included the area at the Tennessee state line in Bristol, and continued to the Exit 19 area of Abingdon.
State police say the interstate became impassable, and several tractor trailers slid off and other vehicles became stuck.
A police spokesperson said highway crews could not keep up with the clearing and state troopers had to help.
For the latest traffic information from the Virginia Department of Transportation, visit www.511Virginia.org.