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.
New York State Route 22
New York State Route 22 (NY 22) is a north–south state highway that parallels the eastern border of the U.S. state of New York, from the outskirts of New York City to the hamlet of Mooers in Clinton County near the Canadian border. At , it is the state's longest north–south route and the third longest state route overall, after NY 5 and NY 17. Many of the state's major east–west roads intersect with, and often join, Route 22 just before crossing into the neighboring New England states, where U.S. Route 7 (US 7), which originally partially followed NY 22's alignment, similarly parallels the New York state line.