Pajares Base Tunnel
The new Pajares Tunnel is a 24,667 m-long railway tunnel under construction in Spain. It will be on the AVE line from Valladolid to Gijón but could be used also by freight trains in the future. The tunnels are affected by major water infiltrations, which currently prevent their being put into use.
It has been announced (17 May 2013) that broad gauge will be used initially to allow immediate use by freight traffic and avoid operational complications. However the sleepers will be gauge-convertible with the eventual change to standard gauge predicted to take a matter of weeks.
25 kV AC electrification will eventually be needed but it is unclear whether this will be the system installed at the opening date.