Just as you might imply from the name, an Interstate is a public access road that crosses state lines. It is a common misconception that U.S. Highways are housed explicitly within one state. Many highways do in fact stay on course across state lines, even while maintaining their numbering. Interstates are exclusively controlled access roads, while highways may vary between controlled and open access. Perhaps more so than any legal or binding standardization, U.S. Highways and Interstates are separated by common characteristics. U.S. Highways, for example, will frequently have stoplights whereas Interstates will only have stoplights in extremely special circumstances. There are a token number of Interstate stoplights that correspond with draw bridges and it is commonplace to come to a complete stop at a tollbooth. Interstates are less subject to change in speeds, largely because U.S. Highways will often travel through the hearts of smaller towns, while it is necessary to exit an Interstate and take a connecting road in order to get through the outskirts of any sub-city sized area. Interstates do provide service to all U.S. major cities. As a generalization, one could say U.S. highway is more conducive to rural travel, meanwhile Interstates serve as a means of traveling within urban areas and from one major city to another.One fundamental difference is where the funds come from to build an Interstate vs. a U.S. Highway. The U.S. Highway system predates the Interstate Highway System, dating back to the 1920′s when individual states came together to connect their roads across state lines. U.S. Highways are state funded initiatives, only receiving federal funds in areas where state lines are crossed or the U.S. Highway joins with an Interstate for a stretch of road.