Which Is the Longest Highway That Serves Seattle
The longest interstate highway in the United States is Interstate 90. It stretches over 3,000 mi which is equivalent to almost 4,800 Km. This goes from Boston to the east coast and further to Seattle on the west coast. This highway actually passes through 15 states. It goes through some of the major cities and also crosses the continental divide of the Rocky Mountains.
http://www.seattle.worldweb.com/SightsAttractions/HighwaysFreeways/
There are two terminus of this highway, the western and the eastern terminus. The western terminus being in Seattle and the eastern terminus being in Boston near the Logan International Airport.
http://en.wikipedia.org/wiki/Interstate_90
