Pretoria Castle (Yard No. 1006) was built by Harland & Wolff in Belfast in 1939 for the Union-Castle Line, a company famous for its lavender-hulled liners that sailed between England and South Africa. After only a few months of passenger service, she was requisitioned by the Admiralty and converted into an aircraft carrier; having all her upper structures removed to enable the fitting of a flight deck. Post war, Pretoria Castle was restored back to her original intended use and placed on the “Round Africa” route. South Africa sponsored a scheme for engineers and their families to emigrate from Britain to fill badly needed positions, so guaranteeing her survival until 1962, when she was retired and broken up.