A "highway" is any public road, street or alley. Then there is the interstate highway system. That system was built mainly with federal money but is maintained by the state, subject to federal rules. It is known as a "limited access highway." Bikes are not prohibited on parts of the interstate system, mostly in the rural areas. In my state, as you approach the urban areas, a sign directs bikes to exit. In some states, but not all, bikes are prohibited on all limited access highways, including the interstate highway system and some state highways that are limited access. The problem with this site is that people go looking for a universal answer.
