4074 'Caldicot Castle' was the second of the class to be built, again as a bespoke example following on from 4073 'Caerphilly Castle' some four months later. The locomotive would play a part in the LNER exchange trials, when the A1 Pacific 4474 'Victor Wild' was compared to it on GWR rails. The locomotive would pass into BR service while retaining its 4074 running number before being withdrawn in May of 1963. The locomotive would not become one of the eight preserved.
The Hornby Castle class is fitted with a five pole motor and simple mechanism resulting in fantastic performance. DCC users are catered for via an 8 pin socket inside the tender with space for a speaker to be fitted. This model features special packaging as part of its position in the celebration of the centenary of the Grouping Act coming into affect, resulting in the start of the 'Big Four' era.