Inside the church tower at Llywel, a set of wooden village stocks hangs on the wall. They were cut in 1798. They share the tower with a plaster replica of the Llywel Stone, a tapered red-sandstone slab close to six feet tall, carved somewhere between the fifth and seventh centuries with a Latin inscription, a line of ogham down one edge, and, on the reverse, geometric and human figures set upside down. The original left the parish in 1878 for the British Museum, where it is catalogued but not currently on display.
St David's is the reason to stop. It stands above the A40 on the side of a small valley running down into the Usk, its purple-sandstone tower a marker you pick out from the road before you see the rest of the village. The body of the church is late medieval, mostly built in the 1480s, with a battlemented west tower that may be older still. Sir George Gilbert Scott restored the church in 1869 and came back for the tower in 1877–78.
Inside there is a round-bowled font from the twelfth century, four surviving portions of a carved screen from around 1500, and a later screen and oak pulpit made by Harry Hems in 1925. A church stood here long before any of it. Gerald of Wales recorded that an earlier building burned around 1188, with nothing saved "except for a box in which the consecrated host was kept."
For food and a bed, the village sends you a mile east to Trecastle and the Castle Coaching Inn, a refurbished coaching inn with a log fire, ten rooms and a bar that keeps local beer. The kitchen runs from beer-battered haddock with mushy peas and tartare sauce to 36-hour pork ribs with pickled chillies and sesame, bavette steak with chimichurri, and a mushroom-and-spinach curry, and finishes on a Welsh cheese board of Perl Las, Perl Wen and Hafod cheddar. Dogs are welcome in the bar but not the restaurant, and there are high chairs if you ask. The inn was named AA Inn of the Year for Wales in 2026.
The nearest proper walk starts at the same turn in Trecastle and climbs to the Usk Reservoir, where a waymarked circuit of 5.4 miles (8.7km) runs around the water and across the dam on wide stone track. It takes about three hours, with one short climb near the start and a stretch of quiet road, and there are picnic tables and views west towards the Black Mountain. Daytime parking by the reservoir is free; the wetter sections turn to mud after rain.
Above all this, on the moor at Y Pigwn, two Roman marching camps overlap beside the old road between Brecon and Llandovery, thrown up on two separate passages of the army in the seventies AD. Their ramparts are low now, but the outlines hold. Lower down, the Gwyn family of Trecastle are said to have flooded the wet meadows between here and the village in the sixteenth century to make a lake and a fishpond, then had themselves rowed to church.
The satirist David Owen, who wrote as Brutus and edited Yr Haul, returned to the church at Llywel and is buried here under a memorial tablet. The railhead is Llandovery, unstaffed, on the Heart of Wales line, with a small free car park; the X80 bus runs Monday to Saturday between Brecon and Llandovery and stops at Trecastle Community Centre — check the current timetable and onward walk before you travel.
The lane beside the church runs along a watershed. Rain falling on one side of it works its way down the Usk and reaches the sea at Newport; rain on the other side goes west down the Tywi to Carmarthen Bay. The gate between them looks like any other.