6. The longest interstate highway is I-90, which travels 3,020 miles from Boston, Massachusetts, to which West Coast city?
From Quiz Interstate Highs and Lows
Answer:
Seattle, WA
I-90 takes the northern route across the U.S., starting at Boston in the east and finishing in Seattle on the West Coast. It passes through a total of 13 states, starting in Massachusetts and then going through New York, Pennsylvania, Ohio, Indiana, Illinois, Wisconsin, Minnesota, South Dakota, Wyoming, Montana and Idaho on the way to its destination in Washington.