20 Francs Pilatus Railway

The Pilatus railway, which opened in 1889, remains the steepest rack railway in the world, with gradients reaching 48 percent on the approach to the summit. Its original locomotives burned coal and had to be purpose-built with boilers mounted at a severe angle simply to keep water covering the firebox on the climb. Swissmint's 2011 commemorative marks the line's continued operation under the Locher rack system — a design unique to this route, using horizontal rack teeth engaged from both sides rather than the more common vertical Abt or Riggenbach arrangements.