Iarnród Éireann (Irish Rail) has commenced works on the Foynes-Limerick rail line as part of a €104m overhaul programme.
The rail operator has already begun the clearance of vegetation along the 42km track, reported RTÉ.
Irish Rail will start key construction work on the rail line in the coming weeks.
Works will include the removal of the old track, followed by the deployment of new rail track and sleepers, as well as the upgrading of road infrastructure at level crossings.
Other works will consist of rehabilitating bridges and culverts, along with renewing the lineside fencing.
Designed to serve the Patrickswell, Adare, Askeaton and Foynes regions, the Foynes-Limerick rail line was first opened as a passenger line in 1858. It was closed in 1963.
The line continued to provide freight services until 2001. It has remained inactive for more than 20 years after falling into disrepair.
With an investment of around €64m, the first phase of the 42km line is expected to be completed in two years.
Under phase two of the project, a signalling system, CCTV at level crossings and train communications systems will be installed on the line.
The works are anticipated to be completed by 2025 and will also cover track connections, as well as upgrades at the Limerick and Foynes yards.
Irish Rail CEO Jim Meade was quoted by the publication as saying: “Our freight services are about creating connections and giving greater opportunity for businesses to switch from road freight to more sustainable rail freight.”