Bon-Accord was built by Andrew Barclay in 1897.
Bon-Accord began its railway career at Aberdeen Corporation Gas Works, where sit remained, until 1964, before being replaced by a diesel; the gas works themselves were closed and demolished in 1975.
It is the oldest running tramway locomotive in the UK. It was used to take coal from the harbour to the gas works on Cotton Street and then take the resulting coke back to the harbour. Because it operated in public areas it was fitted with a skirt and was only allowed to travel at 4mph outside the gasworks whilst it could run at 12mph inside the gasworks.
Under Its skirts the locomotive is an 0-4-0T with 3ft 2in wheels and 12in x 20in cylinders.
Saved for preservation in 1972 it was, initially, stored at Ferryhill along with Mr. Therm and No.3, before being moved to Brechin.
Bon-Accord returned from Brechin to Aberdeen, in 1999, for restoration work to be undertaken by the Bon-Accord Locomotive Society. It was returned to steam in 2008 and in 2010 moved to the Royal Deeside Railway’s base at Milton of Crathes.
After returning to steam again in June 2016 at the Royal Deeside Railway the locomotive spent twelve months at Beamish and also visited Locomotion, the National Railway Museum at Shildon.
By early 2018 the locomotive was back at the Royal Deeside Railway where it was being dismantled as the first stage of its overhaul commenced.
In November the boiler was sent to Locomotive Services Ltd at Loughborough for a ten year overhaul. It was returned and fitted to the frames in March 2019.
The locomotive was reported to be operational in the summer of 2020.