Until the 1950s, Swiss banknotes showed no security features whatsoever. But in 1956 new banknotes were put into circulation, which were produced on the latest security levels – they were printed on fluorescent paper. For the first time, a 10-franc note was issued then – the purchasing power of the Swiss franc had declined to a level that made it appropriate to offer a new denomination. The Swiss poet Gottfried Keller is shown on the obverse of this note. The reverse depicts a typical Swiss mountain plant, the creeping avens. The illustration was designed by the graphic artist Hermann Eidenbenz.