Major Sligo Road Scheme Nears Completion

The key N4 Collooney to Castlebaldwin Road Project in Sligo is close to reaching completion, with the route expected to open to traffic in the coming weeks.

This new Type 2 Dual Carriageway between Collooney and Castlebaldwin will be one of the most significant road projects ever built in the Northwest Region. It will provide approximately 15km of new national road, built to the highest safety, environmental and infrastructural standards, and will change the future of Sligo. The new N4 will be part of a key strategic link between Dublin and Sligo, and will also open up the N17 Atlantic Economic Corridor network. It has the potential to be a game changer – by helping to boost the local economy, bring jobs to the region and make Sligo a better and safer place to live, travel, and work.


Construction on the mainline is substantially complete with snagging, fencing and safety works being completed at present. Other works will be ongoing until Q4 2021, including the construction of a roundabout in Castlebaldwin Village at the junction of the old N4 and the new L-1404 local road as well as a few service crossings. These works will have minimal disruption to the N4 national road traffic.

The new road ties into the existing N4/N17 Toberbride Roundabout on the northern end. A compact grade separated junction is provided approximately midway along the 15km realignment at the local road L-1502 which will facilitate access to the local towns of Ballymote and Riverstown as well as the surrounding areas. A roundabout junction is provided to the southeast of Castlebaldwin village where the cross section of the new road changes from a Type 2 Dual Carriageway to a Single Carriageway on the Boyle Dublin side of this roundabout to tie back into the existing N4.      

When complete, the scheme will significantly improve safety, by reducing the number of fatalities and injuries on the N4 and the existing surrounding local road; reduce inter-urban journey times and improve journey time reliability; and provide a corridor of transport infrastructure that will encourage and support existing investment and employment in Sligo and the Northwest.

The N4 Collooney to Castlebaldwin Road Scheme was included in the Building on Recovery: Infrastructure and Capital Investment Capital Plan 2016-2021, as a key priority in the roads programme which will support economic growth.