What is an interstate highway sign's color?

Interstate highway signs are predominantly blue and white. The blue background signifies the availability of services and facilities, while the white lettering or symbols provide important information to drivers. This color scheme is designed to be easily recognizable and to convey essential information in a clear and effective manner.

While the other color combinations are used for different purposes—such as red and white for stop signs or yield signs, green and white for direction and distance signs, and yellow and black for warning signs—blue and white are specifically designated for interstate highways to guide travelers effectively on long-distance routes across states. Thus, understanding this specific color association helps drivers navigate the interstate system accurately.