Llanfilo is a small village that lies on the north side of Allt Filo, one mile above the A470 between FelinFach and Talgarth. Deserted village remains have been located in the fields surrounding Llanfilo, suggesting the village was once bigger than it is now: A small circular earth and stone mound located on the east-west ridge is thought to have been the remains of a medieval windmill.
Llanfilo is home to St Bilo (Beilo) church, which is known to have a Norman edifice with walls dating back to the 13th Century, indicating the village roots dating back to the medieval period. The church tower was rebuilt in 1881, and the body restored in 1913. The Romanesque lintels are the earliest furnishings from the 12th century, the roof from the 15th century, and the bell believed to be the oldest surviving in the country.
Church service at St Bilo Church is held at 11am on the 1st, 3rd and 5th Sunday for Holy Eucharist, and the 2nd and 4th Sunday for Morning Prayer.