Builth Wells is a market community and area in the region of Powys as well as historical region of Brecknockshire (Breconshire), mid Wales, lying at the convergence of rivers Wye and also Irfon, in the Welsh (or upper) part of the Wye Valley. It has a population of 2,568. Much of the town's structures, consisting of the 1876 Market Hall, were built from rock from Llanelwedd Quarry. Much of the dealing with and also other dressed rock utilized in the construction of the Elan Valley dams was also quarried here. 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 combines bu be, similar to some Middle English orthography), indicating "ox" with gellt (later gwellt), implying "lea or leas"; the very same kind is used despite sex of the animal. The town included "Wells" in the 19th century when its springs were advertised as a visitor attraction. Its modern Welsh name Llanfair-ym-Muallt indicates "Saint Mary in Ox Leas".