The official description of the R105 from the Roads Act 1993 (Classification of Regional Roads) Order 2012[2] reads:
R105: Dublin - Howth, County Dublin
Between its junction with R138 at OConnell Street in the city of Dublin and its junction with R106 at Sutton Cross in the county of Fingal via Eden Quay, Beresford Place, Memorial Road (and via Talbot Memorial Bridge, Georges Quay and Burgh Quay), Amiens Street, North Strand Road, Annesley Bridge Road, Fairview and Howth Road in the city of Dublin: Dublin Road, Sutton; Sutton Cross, Howth Road; Harbour Road and Abbey Street at Howth; Thormanby Road, Carrickbrack Road and Greenfield Road in the county of Fingal.