Interstate 90, commonly referred to as I-90, stretches from Boston, Massachusetts to Seattle, Washington, over 3,000 miles – and all of it is non-stop driving if that is what you want. No stoplights, no cross streets, and no designed delays at all. I-90 runs through thirteen different states, some for shorter stretches than others, but a trip on I-90 will let you see quite a cross-section of the United States. Some of the major cities you'll see on a trip across the country via I-90 are: Boston, Syracuse, Albany, Buffalo, Erie, Cleveland, Toledo, Chicago, Madison, Rapid City, Sheridan, Billings, Missoula, Spokane, and Seattle.
I-90 begins in the east in Boston, Massachusetts and heads west through Worcester, Springfield, and Pittsfield (traveling over 123 miles) before entering the state of New York. Nearly all of I-5 in New York is a toll road as it forms the eastern west portion of the New York State Thruway. A spur route connecting to I-90 here and given the number I-990 is the highest numbered Intersate in the country. I-90 in New York runs for over 385 miles and takes you through Albany, Schenectady, Utica, Syracuse, Rochester, and Buffalo and then takes you into Pennsylvania.
Its shortest stretch in any of the states it passes through, I-90 is only inside the borders of the State of Pennsylvania for a little over 46 miles. I-90 does take you through Erie, Pennsylvlania before it readies itself for a 244 mile long march across the State of Ohio. While in Ohio, the freeway speeds through Cleveland and Toledo before depositing travelers in Indiana. As it goes through Cleveland I-90 forms part of the Innerbelt freeway system, including the corner known as Deadman's Curve – an almost 90 degree.
I-90 stays in Indiana for 156 miles and drives through South Bend (home of the University of Notre Dame) and Gary before entering the State of Illinois. While it is driving across the northern part of Indiana, it is only a short ways from the Michigan border. Illinois is home to only 123 miles of I-90, but the Interstate does go through its largest city here; Chicago. I-90 continues through Rockford, Illinois before running north for the first time into Wisconsin.
I-90 stays in Wisconsin for almost 190 miles and passes through the communities of Beloit, Janesville, Madison, Wisconsin Dells, and La Crosse before taking a long run across the State of Minnesota. I-90 Crosses the Mississippi River while in Minnesota and runs close to, and parallel to, the Iowa state border. The freeway runs for 275 miles in Minnesota before it enters South Dakota near Sioux Falls.
I-90 spends its second highest amount of miles in one state in South Dakota, stretching 412 miles from the east and west borders of the state. The freeway enters Wyoming just after passing through Rapid City and Sturgis, South Dakota. After passing through the cities of Gillette and Sheridan, the roadway turns northwest and heads towards Montana. Interstate 90 is inside the State of Wyoming for a total of 208 miles.
The Interstate covers more miles inside the borders of Montana than in any other state with a total of 551 miles covered from the time it leaves Wyoming to the time it enters Idaho. For a time, while in Montana the speed limit on I-90 was officially "reasonable and prudent". Following the freeway through Montana will take you through Billings, Bozeman, Butte, and Missoula before exiting the state via Lookout Pass and entering Idaho. I-90 only travels 73 miles through Idaho but because it cuts across what is known as the Idaho Panhandle you can say that it crosses the entire state from east to west. Inside Idaho I-90 passes through Wallace, Kellogg, Coeur d'Alene, and Post Falls before entering Washington State. The original plan for the freeway intended for the town of Wallace to be wiped out by the roadway. Town leaders took the step of getting the town and its historic buildings listed on the National Register of Historic Places, thus forcing the government to move the freeway north and elevate it above portions of the town. Wallace, Idaho was home to the last stop light on I-90, it was removed in 1991 to make the Interstate truly non-stop travel from coast to coast.
Washington State is the end of the road for I-90, but there is still almost 297 miles to go before the freeway ends in Seattle. I-90 enters the eastern portion of Washington near Spokane and then takes a gentle turn southwest towards the center of the state before turning northwest again to cross the Cascade Mountains and reach Seattle on the other side.
Over 3,000 miles and 13 states are covered by I-90, the longest stretch of Interstate Freeway in the country.