Dartmouth Castle was placed in the care of the Office of Works in 1909, although the War Office retained the right to use the structure. It was finally placed in State Guardianship in 1970.
B.H. St. John O’Neil wrote the first guide to the castle in 1934, followed by a paper guide in 1951. It was followed by a Ministry of Public Buildings and Works souvenir guide in 1965. This was written by A.D. Saunders. The printer was W.S. Cowell of the Butter Market, Ipswich. This guide took the format: Introduction; Early Defences; The Building of the Castle; Kingswear Castle; Bayard’s Cove; Sixteenth-Century Repairs and Additions; The Civil War; Later History; Description.
Saunders’ guide continued into the period of English Heritage. It was reprinted in 1983, with a second edition in 1988. This carried the branding of Gateway supermarkets. The format was altered, starting with a description and then the history. An expanded third edition appeared in 1991.