A pond just south-west of the medieval castle mound (NPRN 276054) is thought to be the site of the medieval St Teilo's well, thought to be associated with the early medieval/medieval Llangwathen Chapel (NPRN 422397). Ffynnon Ddewi lies soem 440m north-north-east.

Sources incude:
Dyfed Archaeological Trust HER

N Vousden, 13 December 2017