The Dublin to Sligo main line is a railway route operated by Iarnród Éireann in Ireland. It starts in Dublin Connolly station, terminating at Sligo Mac Diarmada railway station in Sligo. The route is a double-track railway as far as Maynooth, being a single-track railway with passing loops between there and Sligo.

Sligo railway station, also known as MacDiarmada station, is a mainline railway station which serves the town of Sligo in County Sligo, Ireland. It is a terminal station which now has two platforms and an intermediate carriage siding. The railway at the station is elevated above the surrounding streets and the station building dominates its surrounds. There is a passing loop at the approach to the station. It is named after Irish patriot Seán Mac Diarmada. Iarnród Éireann, Ireland's national railway operator, runs inter-city rail services between Sligo and Dublin on the Dublin-Sligo railway line.