The tunnel has a low maintenance, ballast-less track where the rails are set in a bed of concrete. When we visited the tunnel, it resembled a workshop with sounds of grinding, welding and other shop floor activity due to maintenance work inside. The tunnel is nearly in a straight line and we were told that it is possible to see the other end of the tunnel as a bright dot of light when the illumination lamps are switched off. 18th April 2008