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All walksYstradgynlais & the South

Ystradgynlais & the South

Sarn Helen and the Roman Fort

A stretch of the Roman road that ran the length of Wales, and the earthworks of the fort at Coelbren beside it.

Distance
4.0 mi / 6.5 km
Time
2 hr 20
Ascent
200 m
Difficulty
Moderate
Shape
Circular

Where it is

The circle shows the general area, not the exact start. Use the directions link below to get to the car park itself. Contours and paths shown are OpenTopoMap, drawn from OpenStreetMap data.

The route

Follow the line of Sarn Helen north out of the village onto the open ground, visit the fort earthworks, and return by field paths and tracks. Straightforward, with the Roman line clear in places.

Worth knowing

  • The fort is earthworks only, but the shape is unmistakable once you know what you are looking at.
  • The Roman road is visible as an agger, a raised bank, along several stretches.
  • Boggy sections on the moorland part; the Romans built above the wet ground for a reason.

What you’ll see

The agger of the Roman road, fort earthworks, and open moorland.

Background

Sarn Helen ran from Neath to Caernarfon, linking the Roman forts of Wales. The name is traditionally associated with Elen, wife of the emperor Magnus Maximus, though the connection is legendary rather than historical.