Cross-border workers from France, and anyone travelling from the south via Bettembourg, will be affected. From 16 July to 15 September, trains on the Luxembourg-Bettembourg route will be suspended so the final phase of the new line can be completed.
The new Luxembourg-Bettembourg line is one of the biggest projects the Luxembourg National Railways Company (CFL) has undertaken in recent years.
When it opens in 2027, many more passengers will be able to travel between France and Luxembourg City, with seat capacity rising from 13,500 to 22,500 by 2030.
The new tracks are being built alongside the widening of the Dudelange motorway, and both projects are meant to ease congestion on routes between Luxembourg and the south.
Work on the line began more than a decade ago, but its complexity means more time is needed. Rui Raimundo, head of CFL infrastructure projects, said 6.4km of track will be finished by the end of this year, but the key southern section connecting to Bettembourg station is still outstanding.
It includes a grade separation, known as a "saut-de-mouton" ("sheep jump"), a small bridge that lets one railway line cross above or below another.
"At this location, the existing tracks are in the way, so we have to shift them sideways to make room for the permanent connection to Bettembourg station", Raimundo said. This requires a complete shutdown.
The closure means another summer of severe disruption for the 12,000 cross-border commuters from France. Once finished, though, the new line will be reserved for cross-border passenger services.
CFL Director Marc Wengler said each line will be able to operate independently, with no need for tracks to cross. Trains from France via Bettembourg and those from Esch-sur-Alzette will each have their own tracks and platforms at Luxembourg station, so a disruption on one will no longer affect the other.
Up to eight trains per hour will be able to run between Luxembourg City and the south or France. Timetables are expected to become far more punctual, in time for the start of the 2027 school year.
