Dublin – Cork Main Line William Dargan, Ireland's foremost railway contractor, built much of the 's main line and a number of its other routes. The directors chose to begin by construction of the stretch of the Dublin – Cork main line as far as Cherryville Junction just west of and the branch to with contracts shared between McCormack and Dargan. Work began in January 1845 with services commencing on 4 August 1846. Trains were scheduled to take about 2hr 35min for the stretch to Carlow and coach connections were arranged to Kilkenny, Clonmel, Waterford and the evening mail coach for Cork. In July 1848 the main line reached , where it met the
Waterford and Limerick Railway and thus linked Dublin and by rail. In October 1849 the main line reached the outskirts of Cork, where the opened a temporary terminus at
Blackpool. The final of line from Blackpool to the centre of Cork includes a tunnel and was not completed for another six years. Services through the tunnel began in December 1855, running to and from a second temporary terminus beside the
River Lee. Finally the present terminus in Glanmire Road opened in July 1856.
Expansion and competition The
Irish South Eastern Railway (ISER) opened between the station at Carlow and in 1848 and reached Lavistown in 1850. From the outset the was worked by the . The
Waterford and Kilkenny Railway (W&KR) had already reached Lavistown, and thus completion of the enabled services to reach . The reached in September 1854 but its relations with the were poor, which impeded traffic between Dublin and Waterford by this route. In 1877 the took over the
Central Ireland Railway and became the Waterford and Central Ireland Railway. The took over the W&CIR in 1900, thus belatedly bringing the rail route between Dublin and Waterford under the control and operation of a single company. The competed with the
Midland Great Western Railway (MGWR) for many years. Both ran services between Dublin and the west of Ireland: the running southwest to Limerick, Cork and Waterford, and the running west to ,
Westport, , and . The also had designs on rail traffic to the west of Ireland. In 1859 the opened a branch line from the Dublin – Cork main line to where it connected with the 's Dublin – Galway main line. In the latter half of the 20th century
Córas Iompair Éireann made this branch part of its Dublin – Galway main line.
Waterford, Limerick and Western Railway In 1901 the bought the
Waterford, Limerick and Western Railway, which gave it both the Waterford – Limerick – Athenry – Claremorris – Collooney cross-country route and the
North Kerry line and branches. The WLWR, recently dubbed the
Western Rail Corridor, crossed territory. It complemented the radial lines from Dublin, enabling Limerick – Galway and Galway – Sligo traffic, and linked intermediate destinations in the west of Ireland. For a very short time the exercised
running powers over the Athenry – Limerick section of this route.
North Wall extension The line was opened in 1877 to resolve limitations with the neither having rail access convenient to the cattle market at
Cabra nor to the docks at
North Wall where there was a requirement for goods, cattle and passenger services. The
London and North Western Railway (LNWR) was supportive of the venture as was the rival
Midland Great Western Railway (MGWR) who were to receive tolls for part of the route. The branch opened on 2 September 1877 diverging from the main line at Islandbridge Junction before tunneling under
Phoenix Park to Cabra where cattle sidings and pens were constructed. After passing under the line to and the 's Liffey Branch to North Wall the route curved back to join the at Glasnevin Junction. Joint running rights were obtained over the route until Church Road junction in the North Wall complex, after which the route diverged to the 's new cattle pens and sidings. Link spurs were available at Newcomen Bridge to
Amiens Street station and to the station at North Wall for passenger ships to Great Britain.
Drumcondra link line The connection to the
Dublin, Wicklow and Wexford Railway (DW&WR) was facilitated in 1891 by the opening of the Dublin loop line from
Westland Row with additional traffic to the Liffey branch line. The eventually moved on an opportunity to open an alternative route line from at what was to be known as Drumcondra junction which diverged just before the junction to the at Glasnevin. The route ran to the north of
Croke Park then rejoined the just before Church Road junction in the North wall complex allowing the same access at North Wall for services. Opening on 1 April 1901 it avoided the 's Liffey branch tolls. A spur from the Drumcondra link line to the at Amiens Street was finally realised on 1 December 1906. ==GS&WR hotels==