Gotthard Base Tunnel

AlpTransit Gotthard AG is responsible for construction. It is a wholly-owned subsidiary the Swiss Federal Railways (SBB-CFF-FFS).
To cut construction time in half, four access tunnels were built so that the construction the tunnel could start at four (a fifth was added later) different sites simultaneously (Erstfeld, Amsteg, Sedrun, Faido and Bodio).
The tunnels are joined approximately every 325 m (1,066 ft) by connecting galleries.