The official definition of the R805 from the Roads Act 1993 (Classification of Regional Roads) Order 2012 states:[1]
R805: Ellis Quay - Finglas, Dublin
Between its junction with R148 at Ellis Quay and its junction with R102 at River Road via Blackhall Place (and via Hendrick Street), Stoneybatter, Manor Street, Prussia Street, Old Cabra Road and Ratoath Road all in the city of Dublin.