A one-off purchase in 1875 from Beyer, Peacock & Co., of similar design to No.4 Loch and No.5 Mona the previous year, this locomotive took its name from a character in Sir Walter Scott's novel Peveril Of The Peak which was enormously popular at the time.  The name is also a local one and it is perhaps apt that she saw extensive use on Peel Line for many years.  The first new boiler was fitted to the locomotive in 1893 with another following in 1911, at which time it was also was rebuilt as a medium-boiled locomotive.  Both boilers were supplied by Beyer, Peacock & Co., with the third and final boiler arriving in 1932.  Surviving in service until 1960 when it was withdrawn from service, it spent its final years on reduced pressure as station pilot; it was placed into storage until, in 1967, it was repainted by the fledgling Supporters' Association and placed on static display at St.John's Station until 1968 when the display was relocated to Douglas Station the following year.  Stored for several years together with No.5 Mona in old carriage shed, it was removed from here and cosmetically restored by members of the Supporters’  Association in the early weeks of 1995.

The locomotive was stripped and repainted into the post-war Indian Red livery and displayed during photography events and later became resident in the railway museum at Port Erin taking the place of No.4 Loch which returned to service following the Association's Un-Loch Your Cash appeal.  The locomotive has since been on display but during 2020 it was temporarily removed from the museum to allow decontamination of asbestos to take place.  No.6 was again returned to the museum during 2022 and the cosmetic work from 1994 was revisited when the Association funded another repaint, the locomotive now in a winter appearance with replica snow plough and canvas cab dodgers.  Upon completion of cosmetic work on No.5 Mona it is currently planned to swap the two, to allow repainting of the wheels and motion of No.6 and rotate the museum displays to keep the exhibition hall fresh.