Portmarnock lies on the coast between Malahide and Baldoyle, along the northern commuter railway line out of Dublin (also the Dublin-Belfast line); Portmarnock railway station opened on 25 May 1844,[REF] is now on the DART network [REF].
Portmarnock lies in the Dublin North-East[REF] Dáil Éireann constituency and in the modern administrative county of Fingal [REF].