An aerial view shows a giant signpost showing the distance to the Swiss nuclear power plant Beznau, the oldest operating in the world, placed by environmental protest group Greenpeace on a field on the approach to Zurich airport near Niederglatt, Switzerland, April 22, 2016. On the field on the right is seen an advertizing of Swiss knife manufacturer Victorinox. REUTERS/Arnd Wiegmann TPX IMAGES OF THE DAY