South Ridge (Allt Maenderyn) up Snowdon (Yr Wyddfa): route map, distance and time

1,085 m · Snowdonia

Yr Wyddfa (Snowdon) is the highest mountain in Wales, with a choice of well-made paths, a mountain railway and a café on the summit.

Leaves the Rhyd Ddu Path for the quieter south ridge over Allt Maenderyn, then climbs the narrow, exposed crest of Bwlch Main to the summit.

South Ridge (Allt Maenderyn) starts at about 190 m and gains 860 m over 6.5 km to 1,040 m on the track. The first 3 km are the easy part, averaging 8%. The steepest kilometre is the one ending at 6.5 km, which climbs 118 m at an average of 22%, with a 500 m stretch from 5 km at about 27%. That last pull ends at the summit. About 25% of the way is steeper than 1 in 5, so expect hands-on-knees going and a slow descent.

South Ridge (Allt Maenderyn) at a glance

Distance	6.5 km one way, to the top
Ascent	900 m
Climb on the track	860 m up, 10 m down on the way
Start and top of the track	190 m to 1,045 m (summit 1,085 m)
Steepest 500 m	About 27%, from 5 km
Steeper than 1 in 5	25% of the way
Time up	2h 50m by Naismith's rule
There and back	4h 5m, down the same way
Grade	Hard
Start	Rhyd Ddu station car park, LL54 6TN
Start grid reference	SH 570 526
Summit grid reference	SH 609 543
Parking	Pay car park beside Rhyd Ddu station on the Welsh Highland Railway.
Bus	Sherpa'r Wyddfa buses link all the main starts round the mountain.

South Ridge (Allt Maenderyn) map

The track from the start (green) to the summit (blue), with a marker at each kilometre.

Height profile and getting to the start

Start 191 m6.5 km to the top

Start grid ref SH 570 526 · Driving directions · By bus or train

Near the start

From OpenStreetMap, within 2 km. Check opening times before you rely on them.

Download the South Ridge (Allt Maenderyn) GPX

Ascent only: plan your way down. A planning track, not checked on the ground; it doesn't show safe scrambling moves. Track data © OpenStreetMap contributors (ODbL), heights from a terrain model.

South Ridge (Allt Maenderyn) kilometre by kilometre

Height, climb and average gradient for each kilometre of the track, with a grid reference at the end of each one to check your position on the map.

At	Height	Climb	Gradient	Grid ref
1 km	264 m	+74 m	7%	SH 578 525
2 km	338 m	+74 m	7%	SH 587 524
3 km	436 m	+97 m	10%	SH 596 521
4 km	568 m	+132 m	13%	SH 604 523
5 km	751 m	+183 m	18%	SH 604 531
6 km	921 m	+170 m	17%	SH 606 540
6.5 km	1,040 m	+118 m	22% steep	SH 609 543

How long South Ridge (Allt Maenderyn) takes

Pace	To the top	There and back
Brisk 6 km/h, 8 min per 100 m up	2h 15m	3h 20m
Steady (Naismith) 5 km/h, 10 min per 100 m up	2h 50m	4h 5m
Relaxed 4 km/h, 12 min per 100 m up	3h 25m	5h 5m

Times leave out stops. Coming down the same way, the table counts the ascent once; steep descents on rough ground can be as slow as the climb.

Today: sunrise 07:48, sunset 18:14. Start by 13:09 to be down before dark, allowing 4h 5m for the walk and an hour for stops.
Tomorrow: sunrise 07:50, sunset 18:12. Start by 13:07 to be down before dark, allowing 4h 5m for the walk and an hour for stops.

Snowdon summit weather for this route

Marginal Today Sunday 18 October

Partly cloudy, up to 4°C at the summit, feeling as cold as -6°C, summit wind 27 mph gusting 33 mph, 0% chance of rain. Rated Marginal. Sunrise 07:48, sunset 18:14.
Poor Tomorrow Monday 19 October

Moderate drizzle, up to 5°C at the summit, feeling as cold as -4°C, summit wind 41 mph gusting 51 mph, 90% chance of rain. Rated Poor. Sunrise 07:50, sunset 18:12.

Best day of the next seven for South Ridge (Allt Maenderyn): Sunday 18 October, with summit gusts around 33 mph and a 0% chance of rain.

Cloud inversion tomorrow morning: 0% (Low), best around 05:00. 7-day inversion outlook.

Hour-by-hour Snowdon forecast · 14-day forecast · Is it safe to climb Snowdon?

Before you go, also check: MWIS Snowdonia forecast · Met Office mountain forecast and hazards · Yr Wyddfa ground conditions report.

What to take today

An insulated jacket, hat and warm gloves: it feels like -6°C on top.
A waterproof jacket. It can rain on the tops in any forecast.
A windproof layer, and poles for balance in gusts to 33 mph.
Microspikes for icy paths. In snow, an ice axe and crampons and the skills to use them.
Map and compass, and the skills to use them. A phone is a backup, not a plan.
A head torch, food, water, a charged phone and a small first aid kit.

About Snowdon

Green ridge below the summit of Yr Wyddfa looking down to Llyn Llydaw, with the pointed top of Crib Goch on the left — From near the summit towards Llyn Llydaw, with Crib Goch on the left. Photo: Julian Herzog, CC BY 4.0.

Yr Wyddfa (Snowdon) is the highest mountain in Wales, with a choice of well-made paths, a mountain railway and a café on the summit. More about Snowdon, with the live forecast.

On the lists: Furth, Hewitt, Nuttall, Marilyn, historic county top, county top.

Extend the walk: tops near the summit

Crib y Ddysgl (1,065 m), 0.8 km north
Crib Goch (923 m), 1.6 km north-east
Y Lliwedd (898 m), 1.6 km south-east
Y Lliwedd East Top (893 m), 1.8 km south-east
Lliwedd Bach (819 m), 2.1 km south-east
Llechog (720 m), 2.4 km north

Challenges that include Snowdon

More walks from Rhyd Ddu station car park

Routes in Peakify's guides that start within 500 m of this one, for another day from the same car park.

From Rhyd Ddu up Mynydd Mawr
Rhyd Ddu via Ffordd Ddu and Bwlch Cwm Llan up Yr Aran

Other routes up Snowdon

Route	Distance	Ascent	Time up	Grade
Llanberis Path	6.9 km one way	979 m	3h 0m	Moderate
Pyg Track	5.3 km one way	740 m	2h 20m	Moderate
Miners' Track	6.8 km one way	770 m	2h 40m	Moderate
Rhyd Ddu Path	5.9 km one way	900 m	2h 40m	Moderate
Snowdon Ranger Path	6.4 km one way	940 m	2h 50m	Moderate
Watkin Path	6.5 km one way	1,015 m	3h 0m	Hard
Crib Goch	5.1 km one way	880 m	2h 30m	Scramble
Y Lliwedd traverse	7.0 km one way	723 m	2h 35m	Scramble
Fox's Path and Crib Goch North Ridge	6.5 km one way	723 m	2h 30m	Scramble
Crib Goch North Ridge from Blaen y Nant	5.3 km one way	903 m	2h 35m	Scramble

In an emergency

Call 999, ask for the police and then mountain rescue. Give your location (the start is at SH 570 526, the summit at SH 609 543), what happened and how many are in your group. If you have no signal for a call, a text to 999 works once you have registered your phone with emergencySMS: text "register" to 999 before you go.

South Ridge (Allt Maenderyn): questions and answers

How far is South Ridge (Allt Maenderyn)?

South Ridge (Allt Maenderyn) is 6.5 km one way to the summit of Snowdon, with 900 m of ascent. There and back by the same way is about 13.0 km.

How long does South Ridge (Allt Maenderyn) take?

About 2h 50m to the summit of Snowdon and 4h 5m there and back by Naismith's rule (5 km/h plus 10 minutes per 100 m of ascent), before stops. A relaxed group takes nearer 5h 5m for the round trip.

How steep is South Ridge (Allt Maenderyn)?

The steepest 500 m averages about 27%, starting 5 km from the start, and 25% of the way is steeper than 1 in 5. South Ridge (Allt Maenderyn) climbs 860 m in all on the track.

Where do you park for South Ridge (Allt Maenderyn)?

South Ridge (Allt Maenderyn) starts from Rhyd Ddu station car park (postcode LL54 6TN). The grid reference is SH 570 526. Pay car park beside Rhyd Ddu station on the Welsh Highland Railway. Sherpa'r Wyddfa buses link all the main starts round the mountain.

Is South Ridge (Allt Maenderyn) suitable for beginners?

Not as a first mountain. Peakify grades it Hard: steep, rough ground where a slip matters. Build up on an easier route first, such as the Llanberis Path.

What time should I start South Ridge (Allt Maenderyn) today?

By 13:09 at the latest. Sunset on Snowdon today is 18:14, South Ridge (Allt Maenderyn) takes about 4h 5m there and back, and that leaves an hour for stops. Start earlier in winter or if the forecast turns.

Is there a GPX for South Ridge (Allt Maenderyn)?

Yes. Download it from this page. It is an ascent-only planning track from the start to the summit, plotted on OpenStreetMap paths and not checked on the ground.