Nantlle Ridge from Nebo up Craig Cwm Silyn: route map, distance and time
734 m · Snowdonia
Craig Cwm Silyn is the 734 m high point of the Nantlle Ridge in Snowdonia, with the Great Slab climbing crag and two lakes in the cwm below.
A hard mountain walk to the summit from Llyn Cwmdulyn road-end car park, Nebo.
Nantlle Ridge from Nebo starts at about 233 m and gains 554 m over 5.8 km to 705 m on the track. It is steep from the start: the first kilometre climbs 184 m (18%). The steepest kilometre is the one ending at 1 km, which climbs 184 m at an average of 18%, with a 500 m stretch from 0.5 km at about 28%. The final 0.8 km eases to the top. About 26% of the way is steeper than 1 in 5, so expect hands-on-knees going and a slow descent.
Nantlle Ridge from Nebo at a glance
| Distance | 5.8 km one way, to the top |
|---|---|
| Ascent | 600 m |
| Climb on the track | 554 m up, 79 m down on the way |
| Start and top of the track | 234 m to 717 m (summit 734 m) |
| Steepest 500 m | About 28%, from 0.5 km |
| Steeper than 1 in 5 | 26% of the way |
| Time up | 2h 10m by Naismith's rule |
| There and back | 3h 20m, down the same way |
| Grade | Hard |
| Start | Llyn Cwmdulyn road-end car park, Nebo |
| Start grid reference | SH 487 498 |
| Summit grid reference | SH 525 502 |
| Parking | Llyn Cwmdulyn road-end car park, Nebo |
Nantlle Ridge from Nebo map
The track from the start (green) to the summit (blue), with a marker at each kilometre.
Height profile and getting to the start
Download the Nantlle Ridge from Nebo 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.
Nantlle Ridge from Nebo 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 | 417 m | +184 m | 18% | SH 492 490 |
| 2 km | 593 m | +175 m | 18% | SH 498 484 |
| 3 km | 542 m | -51 m | -5% | SH 507 486 |
| 4 km | 675 m | +132 m | 13% | SH 510 494 |
| 5 km | 670 m | -5 m | 0% | SH 518 499 |
| 5.8 km | 705 m | +35 m | 4% | SH 525 502 |
How long Nantlle Ridge from Nebo takes
| Pace | To the top | There and back |
|---|---|---|
| Brisk 6 km/h, 8 min per 100 m up | 1h 45m | 2h 45m |
| Steady (Naismith) 5 km/h, 10 min per 100 m up | 2h 10m | 3h 20m |
| Relaxed 4 km/h, 12 min per 100 m up | 2h 40m | 4h 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 07:07, sunset 16:53. Start by 12:33 to be down before dark, allowing 3h 20m for the walk and an hour for stops.
- Tomorrow: sunrise 07:09, sunset 16:51. Start by 12:31 to be down before dark, allowing 3h 20m for the walk and an hour for stops.
Craig Cwm Silyn summit weather for this route
There is no recent summit forecast cached for Craig Cwm Silyn right now. The main Craig Cwm Silyn page loads the live forecast when you open it. Open the live Craig Cwm Silyn forecast.
Before you go, also check: MWIS Snowdonia forecast · Met Office mountain forecast.
About Craig Cwm Silyn
Craig Cwm Silyn is the 734 m high point of the Nantlle Ridge in Snowdonia, with the Great Slab climbing crag and two lakes in the cwm below. More about Craig Cwm Silyn, with the live forecast.
On the lists: Hewitt, Nuttall, Marilyn.
Extend the walk: tops near the summit
- Mynydd Tal-y-mignedd (653 m), 1.5 km north-east
- Garnedd-goch (700 m), 1.6 km south-west
- Trum y Ddysgl (710 m), 2.4 km north-east
- Mynydd Drws-y-coed (695 m), 2.8 km north-east
Challenges that include Craig Cwm Silyn
More walks from Llyn Cwmdulyn road-end car park, Nebo
Routes in Peakify's guides that start within 500 m of this one, for another day from the same car park.
- Nantlle Ridge from Nebo up Garnedd-goch
- Nantlle Ridge from Nebo up Mynydd Graig Goch
Other routes up Craig Cwm Silyn
| Route | Distance | Ascent | Time up | Grade |
|---|---|---|---|---|
| Nantlle Ridge from Rhyd Ddu | 5.4 km one way | — | — | Hard |
| Llynnau Cwm Silyn approach | 7.0 km one way | 690 m | 2h 35m | Hard |
In an emergency
Call 999, ask for the police and then mountain rescue. Give your location (the start is at SH 487 498, the summit at SH 525 502), 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.
Nantlle Ridge from Nebo: questions and answers
How far is Nantlle Ridge from Nebo?
Nantlle Ridge from Nebo is 5.8 km one way to the summit of Craig Cwm Silyn, with 600 m of ascent. There and back by the same way is about 11.6 km.
How long does Nantlle Ridge from Nebo take?
About 2h 10m to the summit of Craig Cwm Silyn and 3h 20m 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 4h 5m for the round trip.
How steep is Nantlle Ridge from Nebo?
The steepest 500 m averages about 28%, starting 0.5 km from the start, and 26% of the way is steeper than 1 in 5. Nantlle Ridge from Nebo climbs 554 m in all on the track.
Where do you park for Nantlle Ridge from Nebo?
Nantlle Ridge from Nebo starts from Llyn Cwmdulyn road-end car park, Nebo. The grid reference is SH 487 498. Llyn Cwmdulyn road-end car park, Nebo
Is Nantlle Ridge from Nebo 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.
What time should I start Nantlle Ridge from Nebo today?
By 12:33 at the latest. Sunset on Craig Cwm Silyn today is 16:53, Nantlle Ridge from Nebo takes about 3h 20m there and back, and that leaves an hour for stops. Start earlier in winter or if the forecast turns.
Is there a GPX for Nantlle Ridge from Nebo?
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.