The history of Trecwn in the 18th and 19th centuries is linked with the Barham family, who funded the building of the school in 1877. Barham Memorial School, a Grade II listed building,[3][4] closed in 2001 following the closure of the armaments depot (see below) a few years before.[5]Joseph Foster Barham (1759–1832) and his son Charles Henry Foster Barham (1808–1878) were both members of parliament, Joseph for Stockbridge, Hampshire, and Charles for Appleby.[6][7]
Trecwn was a community in its own right until 2007; however, the population had decreased significantly from 366 to 260 in the years 1980 to 2006, so it was merged into the community of Scleddau from 3 May 2012.[8]
Church
The Llanstinan parish church of St Justinian is a Grade II* listed building of mediaeval origin, rebuilt in the 19th century.[9][10]
RNAD Trecwn is a decommissioned 1100-acre (450 ha) Royal NavyArmaments Depot. It was closed in 1995 with the loss of 500 jobs.[11] Omega Pacific in 1998 tentatively proposed the site could be used for storing low-level nuclear waste, a plan shelved owing to public opposition. In 2001 German company EBV suggested using the site for weapons reclamation.[12][13] In 2003 the owners announced that the tenanted homes on the site would be sold on the open market.[11]
Plans submitted by The Valley (Pembrokeshire) Ltd to build a 25-megawatt biomass energy plant on the site were conditionally approved in 2015,[14] but by August 2018 work, with the promise of 40 jobs, had not been started by current owners Manhattan Loft Corporation, leading to questions by the local councillor.[15]