Due to the extensive development of high-speed railway lines in recent years, and that this type of work regularly requires the construction of long tunnels, Nortúnel has actively taken part in this type of projects, which is one of its main lines of activity. Nortúnel, apart from tunnel construction, is also involved in the construction of the set of units that make up this type of projects (viaducts, walls, tunnels, embankments, underpasses…), as it has highly experienced and well-trained staff to manage projects that vary in type.