The Roman fort of Segontium on the outskirts of Caernarfon was was bequeathed to the National Trust in 1937, and then passed to the guardianship of the Ministry of Works in 1958. George C. Boon of the National Museum of Wales prepared a ‘blue’ MPBW official guide to ‘Segontium Roman Fort’ in 1962 (2nd ed. 1963; 4th impression, 2s 6d). Boon started with a quotation from Robert Carr Bosanquet
, professor of classical archaeology at Liverpool University and a former director of the British School at Athens. The second edition contained a short summary in Welsh (pp. 30-31).
A fifth impression of the guide was issued by the Department of the Environment in 1972 (15 p) with the additional bilingual title on the title page, Caer Rufeinig Segontium, Sir Caernarfon.
Both editions contained a reconstruction of the fort by Alan Sorrell (see also in the blue guide for Caerwent).