St Dyfan's Church is located on the site of the chapel of ease for Llandybie parish. The site of a well, Ffynnon Llandyfan (NPRN 418246), is located in the north-west corner of the churchyard. According to tradition, the water was known for curing paralysis and similar ailments. The well was reputedly popular with pilgrims, and in the early eighteenth century magistrates reportedly found it necessary to suppress unseemly dancing and game-playing there on Sundays. When the site subsequently became non-conformist, the well became a baptismal pool. After the site reverted to Church of England use, people reportedly continued to drink the waters from a skull alleged to be that of St Teilo. It is noted that he waters of the well have since been diverted into a reservoir serving Llandeilo. The rectangular pool was rebuilt in 1864-1865 and has a flight of stone steps leading down to it. It is Grade II listed, and, along with buildings comprising the Llandyfan Farmstead (NPRN 407331), is considered of group historical value with the church. The churchyard walls and gateway (NPRN 418243) are also Grade II listed and almost certainly date to the rebuilding of the church.

By the 1740s the chapel of ease had become a Methodist chapel. However, it subsequently fell back into Anglican use In1860 the chapel was described as still having two ancient lancets with cusps ornamented with flowers.

The current St Dyfan's church was built in 1864-5 to the designs of R. K. Penson. Lady Dynevor and Mrs Du Buisson of Glynhir were the principal donors. Measurements are given as 18.29m x 7.32m. The church is a Grade II listed building, constructed of squared snecked red randstone with flush red sandstone dressings. It consists of nave and chancel, three-sided apse, south porch and vestry. The roof's timber and slate ridge spirelet is an unusual design: a steep slated pyramid with a smaller version above and a slated square base. Both pyramids have a double row of very low timber trefoil openings beneath, like dove-holes, with a slate pent roof on wooden brackets between the rows, giving a layered effect. The interior retains its original fittings. A low screen had been removed by 1868.

Sources include:
Cadw, Listed Buildings Database
www.llandeilo.org
www.readperiodicals.com

N Vousden, RCAHMW, 16 January 2013