Mallet steam locomotive #403, built in 1903 by SLM Winterthur (Swiss Locomotive and Machine Works), is pulling a mixed train through the spectacular Doux Valley. Originally opened in 1891, the narrow-gauge railroad closed in 1968. It reopened in 1969 as a heritage line und operated until 2008. Services were resumed in 2013, two Mallet steam locomotives #403 and #414 are in daily service throughout the summer season.