Longest Rail Tunnels In the World
Guadarrama Rail Tunnel Spain
Guadarrama is the longest twin tube rail tunnel in Spain and fourth longest in the world. The 28.4km tunnel is dug through Sierra de Guadarrama mountain range for the high speed railway between Madrid and Valladolid. The two parallel tunnels are 30m apart, measured from their central axes. The tunnel was constructed between 2002 and 2007 using TBMs built by Herrenknecht and Wirth. Spanish state owned company Administrador de Infraestructuras Ferroviarias (ADIF) sponsored the project. FCC Construction built the northern part of the tunnel.The interior diameter of the tunnel is 8.5m, whereas the excavation diameter is 9.45m. Interconnection passages located every 250m connect the two tunnels. An emergency room located in the middle of tunnel accommodates up to 1,200 people.