The government legislation that defines the R329, the Roads Act 1993 (Classification of Regional Roads) Order 2012 (Statutory Instrument 54 of 2012), provides the following official description:
R329: Knock, County Mayo (Part Old National Route 17)
Between its junction with N17 at Shanvaghera and its junction with N17 at Ballyfarnagh via Knock all in the county of Mayo.[1]