Trowbridge, in Wiltshire, was in the heydays of the Great Western Railway, a very interesting place. It sat at a crossroads where many trains cross East-West and North-South on the GWR lines would stop. Nearby there was the thriving town itself, the Sausage Factory, the Brewery and a most interesting Steam Engine Shed.
The engine shed was originally built during the GWR sadly brief flirtation with Broad Gauge. As such it was a two road shed. After the changeover to Standard Gauge, the shed was remodelled as a three road shed instead. It was the only such shed where this happened.
The engine shed also had a small turntable which was for use with the tank engines used on the branch line that ran out of Trowbridge station. As the curves on the branch were predominantly all right hand turns away from the station, the turntable was used weekly to turn the locos and even out the wear on the loco bearings.