A network of three tunnels consisting of a total of 5 tubes and 22 evacuation galleries excavated in a karst massif, a tunnel mouth over 40 metres high shared by three tunnels in a slope traversed by a geological fault and the presence of a protected species under a viaduct are just a few of the technical, geological and environmental challenges faced by the construction teams of the Bergara railway junction. It is a crucial project that will make it possible to split the high-speed line to connect the centre of the Iberian Peninsula to the three provincial capitals of the Basque Country and to France.
The project to adapt the Astigarraga-Irún line to the international track gauge with the installation of a third rail involves complex adaptation of all aspects of the existing line. This is particularly the case with the Gaintxurizketa tunnel, where an innovative tunnel boring machine, specially designed to allow trains to pass through, is playing a key role in the works. For the works on this line, ADIF has commissioned a team of Ineco engineers and technicians to undertake the project, management and technical assistance.