Princess is an 0-4-0ST+T steam locomotive built by George England for the Ffestiniog Railway in 1863.

In December 1882, The Princess underwent a substantial overhaul and a large cast iron weight was placed over the side tanks and boiler, giving the locomotive extra adhesive weight and the appearance of a saddle tank.

In 1893 it underwent another major overhaul, receiving a full cab and a true saddle tank; at the same time its name was shortened to Princess.

It worked until the closure of the Ffestiniog Railway on 1 August 1946, hauling the last train.

In 2012, Princess was moved out of Spooner's, and in 2013 it was displayed at Paddington Station to commemorate the 150th anniversary of its construction.