The official definition of the R137 from the Roads Act, 1993 (Classification of Regional Roads) Order, 2012[2] states:
R137: Dame Street — Tallaght, County Dublin (Part old National Route 81)
Between its junction with R138 at Church Lane in the city of Dublin and its junction with M50 at Tymon North in the county of South Dublin via Dame Street, Cork Hill, Lord Edward Street, Christchurch Place, Nicholas Street, Patrick Street, New Street South, Clanbrassil Street Lower, Clanbrassil Street Upper, Harolds Cross Road, Terenure Road North, Terenure Place and Templeogue Road in the city of Dublin: and Templeogue Road and Tallaght Road in the county of South Dublin.