Unsigned Highway - Entire Unsigned Route Systems

Entire Unsigned Route Systems

The C, D, and U road systems in the Great Britain road numbering scheme are systems of routes considered less important than B roads and typically left unsigned.

In New York, state-maintained highways that are not part of a signed state route are assigned a reference route designation. Reference route designations are signed only with reference markers, small green signs posted alongside the highway that typically bear the route number on the first line. The reference route system also includes parkways and other named highways (such as the Inner Loop), which are given a reference route designation for inventory purposes.

Oregon maintains a system of state highways separate from its signed state routes. The state highway system is only used in ODOT internal accounting and is not signed.

Pennsylvania maintains a set of minor routes, called quadrant routes, that are not signed with standard confirming markers. Pennsylvania also maintains relocated signed routes, interchanges, wye connections, rest areas, and truck escape ramps as unsigned state highways.