After over a decade of work Swiss engineers drilling the world’s longest tunnel broke through the last section of rock. With a length of 57 km (35 miles) crossing the Alps, the train tunnel should become operational at the end of 2017. The pictures coverage of the final break-through at the Faido-Sedrun section, shooting and transmitting the pictures from the intestines of the earth was a rare and difficult challenge for Zurich based Reuters photographers Arnd Wiegmann and Christian Hartmann.