Castell Dinas

At around 450 metres, on a saddle in the Rhiangoll valley between Talgarth and Crickhowell, this is the highest castle site anywhere in England or Wales.

It is also two monuments occupying the same ground, roughly fifteen hundred years apart.

The hillfort

The Iron Age enclosure came first, using the natural shape of the ridge with multiple ramparts and ditches. It is substantial, and it commands the pass completely — anything moving through the Black Mountains between the Usk and the Wye has to come this way.

The castle

The Normans put a castle inside it in the twelfth century, and they did what anyone sensible would do: reused the existing earthworks rather than digging new ones.

There was a stone keep and a curtain wall, and it was held with the lordship of Brecon. It was fought over during the Welsh wars and appears to have been abandoned by the later fourteenth century, after which the stone went the way of most redundant castle stone.

What survives is earthworks, rubble mounds and fragments of walling. There is not much masonry, and that is not really the point.

Why go

The position. From the top you have the Rhiangoll below, the Black Mountains ridges running away east, Pen y Fan and the central Beacons to the west, and the Usk valley opening south.

Standing there makes the whole strategic geography of southern Powys legible in a way no map does. You can see exactly why an Iron Age community fortified this saddle and exactly why a Norman lord did the same thing on top of their work.

It also makes the point that reoccupation is the norm rather than the exception. Good defensive ground stays good defensive ground, and a great many Welsh castles sit on sites that were chosen by somebody else first — Montgomery under Ffridd Faldwyn, Brecon under Pen y Crug, Crickhowell under Crug Hywel.

Visiting

Free, open access, on common land. Park at the layby on the A479 between Talgarth and Bwlch and walk up; it is steep and takes twenty minutes or so.

There is no interpretation on site and no facilities. Take a map, because the summit is exposed and the weather in the Black Mountains changes quickly.

Talgarth is three miles north, Crickhowell six miles south, and Tretower Court is on the way to the latter.