The chapel of St Mary sits low among a ring of old yews, so dark and hunched that the Victorian diarist Francis Kilvert described it as "squatting like a stout grey owl among its seven great black yews." The present building dates from 1762, with a south porch added in 1817, but the tapered octagonal font inside is medieval, older than the walls around it. There is a west gallery, a pulpit inscribed 1780, a settle dated 1783 and an eighteenth-century oak plank door. Opposite the churchyard stands a red K6 telephone box, a George VI design cast by the Lion Foundry, listed in its own right partly for the company it keeps with the church. Behind the chapel is a former Baptist meeting house, whose inscription records that William and David Prosser brought the Gospel to their house in 1737.
The hamlet lies in the Vale of Ewyas, strung along the River Honddu below the long border ridges of the Black Mountains. The rock here is Old Red Sandstone, which gives the eroded gullies and slopes a ruddy tone rather than the black the name suggests. From the south you leave the A465 north of Abergavenny and take the narrow minor road up through Llanthony. From the north the only way in is over Gospel Pass, the highest public road in Wales, threading between Twmpa and Hay Bluff before dropping into the valley. It is exposed and quick to close in bad weather, so check conditions before you commit to it.
This is walking country before it is anything else. From the hamlet a hard loop climbs Twmpa, better known as Lord Hereford's Knob, a little under seven miles with well over two thousand feet of ascent, following the ridge before returning down the Nant Bwch side valley. Gentler is the path south to Llanthony Priory, about three and a half miles down the valley floor, where the free-to-enter ruins of an Augustinian house founded by 1118 stand open beneath the hills. The waymarked network from Capel-y-ffin also reaches towards Hatterrall Hill, the Beacons Way and Offa's Dyke, though the paths run dense enough that a map matters.
For food and drink you go down to Llanthony. The Cellar Bar occupies the vaulted thirteenth-century undercroft of the priory, all settles and wall panelling, serving food and drink from Tuesday to Sunday, with Felinfoel Double Dragon and Dragon Welsh IPA among the cask beers; recent visitors have eaten beef lasagne and a beef-and-stout chilli cottage pie. Across the field the Half Moon Inn is a plainer walkers' pub with a beer garden and simple food, pizza and toasties and chips, breakfast cobs in the morning, and dogs are welcome.
Serious food shopping means Hay-on-Wye, about eight miles north over the pass in good conditions. Upper Court Farm Butchery on Broad Street, run by Tom and Julie, sells beef and lamb off their own farm alongside home-grown pork, poultry and game, and the Thursday market fills Memorial Square, the Cheese Market, Butter Market and Clock Tower with more than forty traders, bread, fish, cheese, cakes and coffee among them.
Above the hamlet, on the morning-facing slope of Tarren yr Esgob, stand the remains of a stranger venture. In 1869 the Rev. Joseph Leycester Lyne, known as Father Ignatius, began building an Anglican Benedictine monastery here; the cloister followed in 1870 and a detached church in 1872. Work stopped in 1882, and the church collapsed around 1920, leaving only its chancel. In 1924 the sculptor Eric Gill took the place over for a Catholic community of craftsmen. The painter David Jones came with him from Ditchling and stayed until 1928; his watercolour Capel-y-ffin of 1926 to 1927 hangs in the national collection at Amgueddfa Cymru.
The nearest railway is at Abergavenny, twelve or thirteen road miles down the valley, with a taxi rank; check a journey planner before counting on a bus this far up the valley. Once a year an ecumenical pilgrimage still walks between the old priory at Llanthony and the chapel in its yews, the two ends of the same narrow valley.