The North Circular Road - designated as R101 regional road - is an important thoroughfare on the north-side of Dublin. The regional road was long considered the northern boundary of the city and still separates the city centre from the inner suburbs. It runs from the Phoenix Park in the west through Phibsboro, to North Wall in the east and is the location of a number of important institutions, The Mater Hospital, Dalymount Park and Mountjoy Prison are on the North Circular Road and both Croke Park and St. Brendan's Hospital are nearby.
The R101 and the NCR are the same for most of their length; the entire NCR forms a section of the R101. In the west the R101 connects the NCR to Parkgate Street via the short Infirmary Road ; at the eastern end the R101 becomes Portland Row after the junction with Summerhill. It continues the northern loop through Saville Place , then turning east for its final kilometre via Sheriff Street (Upper) before terminating at North Wall Road (the R131).