Unsigned highway

Reference routes are a class of highways in New York that are only identified by small inventory markers like this. This marker is designating New York State Route 940U.
Sign at the junction of U.S. Route 50 with Utah State Route 64 in Holden, Utah. SR 64 is a short connector between US 50 and Interstate 15. This sign emphasizes the connection to the freeway, omitting the actual numbered designation of the road.

An unsigned highway is a highway that has been assigned a route number, but does not bear road markings that would conventionally be used to identify the route with that number. Highways are left unsigned for a variety of reasons, and examples are found throughout the world. Depending on the policy of the agency that maintains the highway, and the reason for not signing the route, the route may instead be signed a different designation from its actual number, with small inventory markers for internal use, or with nothing at all.