A stretch of King Avenue West in Billings just north of Interstate 90 has the distinction of being the busiest road in the state, with about 40,000 vehicle trips a day. Other busy spots include the city’s Main Street as it heads into Billings Heights from downtown, at about 39,000 trips a day, and a stretch of 10th Avenue South in Great Falls that averages nearly 37,000 trips a day.
