A23

A23 is an alphanumeric designation used in multiple transport networks and other systems to identify routes, projects, or parts. The designation is most commonly encountered as a road number in several countries, where the same code can refer to distinct infrastructures.

In road networks, the A23 designation denotes different routes in different countries. In the United Kingdom, the A23 is a major south-eastern trunk road that connects London with the city of Brighton, passing through southern counties and serving as a key corridor into Sussex. In Italy, Autostrada A23 (Tarvisio–Udine–Palmanova) is a northeast Italian motorway that runs from the Austrian border at Tarvisio, passes near Udine, and terminates at Palmanova, where it connects with the A4 motorway. The exact endpoints and connections vary by country, but the common feature is that A23 identifiers designate significant regional highways.

Beyond roads, A23 can appear in other contexts as an identifier for transportation or infrastructure elements such as local bus routes, project codes, or model numbers in consumer electronics and automotive parts. Because alphanumeric route designations are reused in different nations and sectors, the precise meaning of A23 is highly dependent on geographic and domain context.

In sum, A23 most often refers to roadways in multiple countries, with notable examples in the United Kingdom and Italy, while also appearing in varied non-road contexts as a general identifier.