Builth Wells is a market community and also area in the area of Powys as well as historical region of Brecknockshire (Breconshire), mid Wales, lying at the assemblage of rivers Wye and also Irfon, in the Welsh (or upper) part of the Wye Valley. It has a population of 2,568. A lot of the community's buildings, including the 1876 Market Hall, were built from stone from Llanelwedd Quarry. Much of the facing as well as various other clothed rock utilized in the building and construction of the Elan Valley dams was likewise quarried below. The quarry generated the first occurrence of laumontite in Wales. The quarry is presently operated by Hanson Aggregates. Builth is a longstanding anglicization of the Old Welsh Buellt/Buallt which incorporates bu be, comparable to some Middle English orthography), meaning "ox" with gellt (later gwellt), implying "lea or leas"; the exact same kind is made use of regardless of sex of the pet. The community included "Wells" in the 19th century when its springs were advertised as a visitor destination. Its modern Welsh name Llanfair-ym-Muallt suggests "Saint Mary in Ox Leas".