List of Interstate Highways in Washington
Interstate 90 (I-90) is the longest primary Interstate Highway in Washington, which connects Seattle to Spokane and the Idaho border, measuring , while I-82, connecting the Oregon border city of Umatilla to Elensburg via Yakima, is the shortest at . The longest auxiliary Interstate Highway in Washington is I-405, a bypass of Seattle through the Eastside, at , and the shortest is I-705, a spur into downtown Tacoma, at . One route, I-605, has been proposed over the years to form another Eastside bypass, however there are no plans to construct this fifth auxiliary route.
After passage of the Federal Aid Highway Act of 1956, which formed the Interstate Highway System, the American Association of State Highway Officials had approved I-5 and I-90 across Washington on August 17, 1957. I-82 was approved on October 17, 1957, two months after I-5 and I-90, as part of a addition to the Interstate Highway System.
U.S. Route 20 in New York
U.S. Route 20 (US 20) is a part of the U.S. Highway System that runs from Newport, Oregon, to Boston, Massachusetts. In the U.S. state of New York, US 20 extends from the Pennsylvania state line at Ripley to the Massachusetts state line in the Berkshire Mountains. US 20 is the longest surface road in New York. It runs near the Lake Erie shore from Ripley to Buffalo and passes through the southern suburbs of Buffalo, the Finger Lakes, the glacial moraines of Central New York, and the city of Albany before crossing into Massachusetts. US 20 connects to all three major north–south Interstate Highways in Upstate New York: Interstate 390 (I-390) near Avon, I-81 south of Syracuse, and I-87 in Albany by way of Fuller Road Alternate.