IDOM has participated in the design of the entire infrastructure during the tendering process, as part of the consortium led by Salini- Impregilo. Plus, the consortium was the selected tenderer for the works of Line 3, over 41 km long, IDOM being responsible for its entire design: route, tunnel, viaducts and level sections, along with the stations (underground and over-ground, as well as the connection stations with Line 6), workshops, sheds and the road and landscape works necessary for its blending in with the urban environment. The correct coordination between the different disciplines is one of the project keys, a chore which has been eased by the multidisciplinary character of IDOM’s workforce, led from the capital of Saudi Arabia. The project includes the detailed design and the production information of twenty stations, based on the prototypes provided by the client. In the case of underground stations, it has been necessary to develop a whole new prototype, given the width limitations imposed by the narrow streets of the popular Batha neighbourhood. This opportunity has been taken to increase the spatial quality of the stations and to let sunlight in, all to improve the passengers’ orientation and experience.