Nortúnel has taken part in various sections of the metro lines, using various excavation methods (shearers, backhoes, blasting, raise boring…), for the construction of lines, accesses or ventilation shafts and lifts. The suburban lined projects are especially unique due to their placement, as they may affect a large number of individuals during construction. For this reason, experience is vital in order to complete these works in a short time as possible, and while preventing any incidents with the general population.