Map & Elevation
About this Route
This GPX climbs Rhinog Fawr from Cwm Bychan by the Roman Steps, Llyn Du and the north-east side of the mountain, returning the same way. It covers 8.7 km with about 667 m of ascent and usually takes 5 to 7 hours. The distance is moderate, but the Rhinogydd are exceptionally rough: expect heather, boulders, bog and faint paths for much of the day.
Follow the track from Cwm Bychan towards Bwlch Tyddiad, the pass crossed by the so-called Roman Steps. These are a medieval packhorse route rather than Roman paving, and the stones are polished and slippery when wet. Near the top of the pass, leave on the smaller Cambrian Way line and climb through broken walls, heather and rough rock to Llyn Du. From the tarn, pick a careful route through crags and boulders onto Rhinog Fawr's broad 720 m summit.
Return past Llyn Du and down the Roman Steps to Cwm Bychan. This GPX does not continue south along the Rhinogydd ridge or descend into Cwm Nantcol. Paths are intermittent and numerous rock bands end in steep drops, so a direct compass line is not always walkable. Use the GPX with a detailed map, read the terrain and allow far more time than the distance suggests.
From the Roman Steps, the path climbs through heather and rough rocks to the glittering Llyn Du.
The Great Outdoors
Route Waypoints
Start from the recognised parking area near Cwm Bychan. Follow local parking instructions and keep tracks and gates clear.
Take the main route towards Bwlch Tyddiad. The surface becomes rougher as the valley narrows.
Climb the old packhorse paving. Wet stones are polished, uneven and awkward on descent.
Near the top of the pass, take the smaller south-going path through the broken wall towards Llyn Du.
Follow the faint Cambrian Way line through dense heather and boulders. Progress is slow.
Reach the dark tarn beneath Rhinog Fawr. Identify a safe line through the crags rather than climbing the nearest gully.
Reach the broad 720 m summit area. Take a careful bearing back towards Llyn Du.
Retrace Llyn Du, Bwlch Tyddiad and the Roman Steps to the start.
Essential Tips
Rhinog kilometres are slow. Heather, boulders and repeated route choices make a short map distance physically demanding.
Cliffs and rock bands interrupt the slopes. Use bearings for direction, then choose safe ground around obstacles.
The uneven stones are slippery after rain and hard on tired legs. Descend slowly.
Do not continue along the Rhinogydd ridge or drop into Cwm Nantcol unless separately planned.
Frequently Asked Questions
Are the Roman Steps actually Roman?
No, they're a medieval packhorse route, not Roman paving. The name is a bit misleading but it's what everyone calls them.
How long does it take to climb Rhinog Fawr from Cwm Bychan?
Usually 5 to 7 hours for the round trip. The distance is only 8.7 km, but the rough terrain of heather, boulders and bog slows you down significantly.
What makes the Rhinog mountains so difficult?
They're exceptionally rough with dense heather, boulders, boggy ground and only faint paths for much of the route. The terrain makes even short distances slow and physically demanding.