Within Wayfinder, many ways link to official data through a USRN. This is the Unique Street Reference Number. Most roads, tracks and paths in the UK have a USRN. Every way that is Maintainable at Public Expense (MAPE) has a USRN.
Highways Authorities across the country supply information about every street in their area. This information includes the USRN as a key identifier. Supplying the information is a legal obligation on the authority. Introduced primarily to increase efficiency and minimise disruption, USRN's help users with accuracy.
Each USRN comes from the highway authority and is open to scrutiny. Thus, it is reliable and authorities information. Routes with a USRN are recognised ways. Yet, we need to be careful not to believe that a route without a USRN carries no public rights. This is not always the case.
A major use of USRNs within Wayfinder is identifying that way to highway authorities. For example, when reporting obstructions and other problems. In such cases, being sure that everyone is talking about the same way is essential.
As well as USRNs, there are also UPRN (Unique Property Reference Number). Both have been a UK Government requirement since July 2020.