Allt Maenderyn, often anglicised as ‘The South Ridge’, is the mile-long ridge running south from near Snowdon summit, from Clawdd Coch down to Bwlch Cwm Llan. This route to the summit is part of the Cambrian Way (which then goes down from the summit on the Pyg Track).
If descending this way, from the summit you should initially follow the Rhyd Ddu Path (down past the main entrance of the summit building) for the best part of ½ mile, then after the narrow Bwlch Main bear left up over the round hill of Clawdd Coch, to then descend on the grassy top of the ridge. (The name ‘Clawdd Coch’ is shown on some maps, though not the current O.S. map.)
The South Ridge as seen from near the summit (running left from the centre of the picture)
After Bwlch Main the South Ridge Path heads upwards over Clawdd Coch, while the Rhyd Ddu Path skirts round it. If it’s windy and the upper path feels exposed, take the lower one then cut back once round the hill.
Descending on the South Ridge, looking towards the coast
There are great views back to the summit, to Y Lliwedd, and over Cwm Tregalan to the upper Watkin path.
The South Ridge starts near Bwlch Main; the photo below shows the same section. (Ordnance Survey data © Crown copyright and database right 2024)
The South Ridge, from the quarry up to Clawdd Coch and Bwlch Main, where it joins the Rhyd Ddu Path to the summit, as seen from Yr Aran. The well established path up the South Ridge itself is never near the edge.
This good, well-defined path can be combined with the Watkin Path to make a useful return route from the summit (both routes are virtually the same length). On reaching the old slate quarry at the bottom of the South Ridge (see map below), turn left to follow the path down to the old Hafod y Llan quarry tramway, then after ⅓ mile descend to the Watkin Path near the head of the waterfalls, a mile from the start. This round, as shown below, is sometimes called the Cwm Tregalan Loop or Cwm Tregalan Round, as it circles Cwm Tregalan.
The Watkin Path and South Ridge loop. (O. S. data © Crown copyright and database right 2024)
This Allt Maenderyn (South Ridge) route can also be combined with the Rhyd Ddu Path to make a useful return route from the summit. To do this, on reaching the old quarry at the bottom of the South Ridge, turn right down through the quarry (see map below), then along the old quarry access road to Pen ar Lôn, where you will rejoin the Rhyd Ddu Path a mile from the start.
On reaching Bwlch Cwm Llan quarry at the bottom of the South Ridge, turn either left or right to rejoin the Rhyd Ddu or Watkin Paths. (Ordnance Survey data © Crown copyright and database right 2024)
These routes can also be done in reverse, but we much prefer to do it this way, i.e. coming down the South Ridge.
See also: Combining and Mixing Paths on Snowdon