The North Wales Narrow Gauge Railways, which opened in 1877, were built to the unusual one foot 11 1/2 inch gauge. Their first two locomotives were two Single Fairlies, that is, with a power bogie and a trailing bogie. In 1917 both were combined into one working locomotive due to their poor condition. From 1923 it belonged to the Welsh Highland Railway and it is unclear whether they also used it on the Ffestiniog Railway and reduced their height to do so. It was retired in 1937 and not refurbished after the Ffestiniog Railway reopened. 