North-end excavation of Udaliatz underwayOn 18.03.2011 excavation started from the north end of the twin track Udalaitz tunnel on the Mondragon-Elorrio section on the new Vitoria-Bilbao-San Sebastian high-speed line. This 4,440 m section includes two tunnels: Karraskain, 410 m and Udalaitz, 3,160 m. The Udalaitz tunnel, second longest on the line, is being excavated by traditional methods. Excavation from the south entrance started in November 2009, and has reached almost halfway. For more, click here and visit tunnelbuilder archive es/100. 16/11.