One of the most notable buildings in Tonyrefail is Collenna House, a three-story mansion originally built in 1093, which overlooks the village. The house is believed to have been built by the Welsh noble, Einion ap Collwyn who after a dispute with Iestyn ab Gwrgant, married Iestyn's only daughter, Nest. The two are said to have set up home at Collenna House and it was around this time that they founded the old church of St. John.
One of the most recognizable buildings in Tonyrefail is Collenna House, a three-story estate originally built in 1093, which overlooks the village. It is believed that Einion ap Collwyn, a Welsh nobleman, constructed the house after resolving a dispute with Iestyn ab Gwrgant and subsequently married his daughter, Nest. The couple then established residence at Collenna House, co-founding the old church of St. John.