The Daily Post (Llandudno) has published a story explaining Waugh’s connection with the Arnold House school in nearby Llanddulas. In Decline and Fall, Waugh renamed the place Llanabba and called the school after the house:
…It was [here] in January 1925 Waugh arrived at Arnold House on the North Wales coast to take up a teaching post. For the drama, filming was carried out in South Wales at Atlantic College, St Donats Castle, St Donats and Llantwit Major. The house was then a private prep school for boys and Waugh, then aged 21, was struggling to earn a living after Oxford. Headmaster, Mr C P Banks, “a tall old man with stupid eyes”, had offered him a £160-a-year post teaching history, Latin and Greek.
Waugh seized the chance. “Apparently,” he recorded in his diary, “the school is so far away from any sort of place of entertainment that it is quite impossible to spend any money at all there.”… Out of school hours, he lived with two of his four fellow teachers in a nearby building, a house called Sanatorium which was reached by a ‘precipitous’ path between ‘dung heaps, gooseberry bushes and stone walls’. Depressed by the spartan atmosphere at Arnold House he often sought solace in the local pub Fair View Inn – known as “Mrs Roberts’ pub” in both his diaries and in Decline and Fall. …
A more detailed account of a visit to this area may be had on Duncan McLaren’s website where he reports his visit of a few years ago. Since the time Duncan was there, the building that was Arnold House school (now called Ty Delfryn) has been undergoing substantial renovation into what will apparently be several flats when finished. A detailed description of the renovation project is available here. The pub is still there in Llanddulas and Duncan’s site offers several photos. (Thanks to reader Dina Rees for providing a link to the Ty Delfryn website.)
Meanwhile another Welsh publication (WalesOnline) offers information regarding the sites in South Wales where the actual location shooting for the film took place. This describes several specific filming sites, including the beach where Capt Grimes’ unsuccessful suicide was staged (Southerndown Beach in the Vale of Glamorgan). It looks much like the beach in North Wales where Waugh’s own suicidal misadventure took place. Photos of that beach at Llanddulas may be seen in Duncan’s report.