Afon Las from Nant Peris and plateau traverse up Glyder Fach: route map, distance and time
994 m · Snowdonia
Glyder Fach is a rocky Glyderau summit above Ogwen, famous for the Cantilever Stone, Castell y Gwynt and the scramble of Bristly Ridge.
A hard mountain walk to the summit from Afon Las mapped footpath entrance.
The Afon Las from Nant Peris and plateau traverse starts at about 150 m and gains 880 m over 5.1 km to 959 m on the track. It is steep from the start: the first kilometre climbs 363 m (36%). The steepest kilometre is the one ending at 1 km, which climbs 363 m at an average of 36%, with a 500 m stretch from 0.4 km at about 43%. The final 0.1 km eases to the top. About 44% of the way is steeper than 1 in 5, so expect hands-on-knees going and a slow descent.
Afon Las from Nant Peris and plateau traverse at a glance
| Distance | 5.1 km one way, to the top |
|---|---|
| Ascent | 930 m |
| Climb on the track | 880 m up, 75 m down on the way |
| Start and top of the track | 150 m to 982 m (summit 994 m) |
| Steepest 500 m | About 43%, from 0.4 km |
| Steeper than 1 in 5 | 44% of the way |
| Time up | 2h 35m by Naismith's rule |
| There and back | 3h 35m, down the same way |
| Grade | Hard |
| Start | Afon Las mapped footpath entrance, LL55 4UF |
| Start grid reference | SH 615 577 |
| Summit grid reference | SH 656 582 |
| Parking | Nant Peris park and ride car park; the postcode is approximate |
Afon Las from Nant Peris and plateau traverse map
The track from the start (green) to the summit (blue), with a marker at each kilometre.
Height profile and getting to the start
Near the start
From OpenStreetMap, within 2 km. Check opening times before you rely on them.
Download the Afon Las from Nant Peris and plateau traverse 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.
Afon Las from Nant Peris and plateau traverse 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 | 513 m | +363 m | 36% steep | SH 623 580 |
| 2 km | 706 m | +193 m | 19% | SH 632 584 |
| 3 km | 870 m | +164 m | 16% | SH 638 581 |
| 4 km | 943 m | +73 m | 7% | SH 647 580 |
| 5 km | 956 m | +13 m | 1% | SH 655 582 |
| 5.1 km | 959 m | +3 m | 5% | SH 656 583 |
How long the Afon Las from Nant Peris and plateau traverse takes
| Pace | To the top | There and back |
|---|---|---|
| Brisk 6 km/h, 8 min per 100 m up | 2h 5m | 2h 55m |
| Steady (Naismith) 5 km/h, 10 min per 100 m up | 2h 35m | 3h 35m |
| Relaxed 4 km/h, 12 min per 100 m up | 3h 10m | 4h 25m |
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 13:39 to be down before dark, allowing 3h 35m for the walk and an hour for stops.
- Tomorrow: sunrise 07:49, sunset 18:12. Start by 13:37 to be down before dark, allowing 3h 35m for the walk and an hour for stops.
Glyder Fach summit weather for this route
-
Marginal Today Sunday 18 October
Overcast, up to 4°C at the summit, feeling as cold as -5°C, summit wind 26 mph gusting 32 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 -3°C, summit wind 40 mph gusting 50 mph, 90% chance of rain. Rated Poor. Sunrise 07:49, sunset 18:12.
Best day of the next seven for the Afon Las from Nant Peris and plateau traverse: Sunday 18 October, with summit gusts around 32 mph and a 0% chance of rain.
Cloud inversion tomorrow morning: 0% (Low), best around 09:00. 7-day inversion outlook.
Hour-by-hour Glyder Fach forecast · 14-day forecast · Is it safe to climb Glyder Fach?
Before you go, also check: MWIS Snowdonia forecast · Met Office mountain forecast.
What to take today
- An insulated jacket, hat and warm gloves: it feels like -5°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 32 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 Glyder Fach
Glyder Fach is a rocky Glyderau summit above Ogwen, famous for the Cantilever Stone, Castell y Gwynt and the scramble of Bristly Ridge. More about Glyder Fach, with the live forecast.
On the lists: Furth, Hewitt, Nuttall.
Extend the walk: tops near the summit
- Castell y Gwynt (972 m), 0.3 km south-west
- Tryfan (918 m), 1.3 km north-east
- Glyder Fawr (1,001 m), 1.4 km west
- Y Foel Goch (805 m), 2.1 km east
- Gallt yr Ogof (763 m), 2.9 km east
- Y Garn (947 m), 2.9 km north-west
Challenges that include Glyder Fach
- Welsh 3000s · 15
- Welsh 100 Challenge · 100
- Snowdonia 900m Peaks · 16
- Welsh Skyline · 9
- Paddy Buckley Round · 47
- Furths · 34
- Hewitts · 523
- Nuttalls · 442
More walks from Afon Las mapped footpath entrance
Routes in Peakify's guides that start within 500 m of this one, for another day from the same car park.
- Afon Las from Nant Peris up Glyder Fawr
- Llwybr y Carw / Afon Las up Y Garn
Other routes up Glyder Fach
| Route | Distance | Ascent | Time up | Grade |
|---|---|---|---|---|
| Pen y Gwryd via the Miners' Track | 3.9 km one way | 720 m | 2h 0m | Moderate |
| Devil's Kitchen / Twll Du and plateau traverse | 5.4 km one way | 790 m | 2h 25m | Hard |
| Pen-y-Pass ridge approach and plateau traverse | 4.6 km one way | 700 m | 2h 5m | Hard |
| Ogwen via Bristly Ridge | 3.7 km one way | 828 m | 2h 5m | Scramble |
| Senior's Gully and Ridge and plateau traverse | 6.1 km one way | 900 m | 2h 45m | Scramble |
| Y Gribin and plateau traverse | 5.6 km one way | 790 m | 2h 25m | Scramble |
| Bristly Ridge | 3.0 km one way | 690 m | 1h 45m | Scramble |
In an emergency
Call 999, ask for the police and then mountain rescue. Give your location (the start is at SH 615 577, the summit at SH 656 582), 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.
Afon Las from Nant Peris and plateau traverse: questions and answers
How far is the Afon Las from Nant Peris and plateau traverse?
The Afon Las from Nant Peris and plateau traverse is 5.1 km one way to the summit of Glyder Fach, with 930 m of ascent. There and back by the same way is about 10.2 km.
How long does the Afon Las from Nant Peris and plateau traverse take?
About 2h 35m to the summit of Glyder Fach and 3h 35m 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 25m for the round trip.
How steep is the Afon Las from Nant Peris and plateau traverse?
The steepest 500 m averages about 43%, starting 0.4 km from the start, and 44% of the way is steeper than 1 in 5. The Afon Las from Nant Peris and plateau traverse climbs 880 m in all on the track.
Where do you park for the Afon Las from Nant Peris and plateau traverse?
The Afon Las from Nant Peris and plateau traverse starts from Afon Las mapped footpath entrance (postcode LL55 4UF). The grid reference is SH 615 577. Nant Peris park and ride car park; the postcode is approximate
Is the Afon Las from Nant Peris and plateau traverse 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 Pen y Gwryd via the Miners' Track.
What time should I start the Afon Las from Nant Peris and plateau traverse today?
By 13:39 at the latest. Sunset on Glyder Fach today is 18:14, The Afon Las from Nant Peris and plateau traverse takes about 3h 35m there and back, and that leaves an hour for stops. Start earlier in winter or if the forecast turns.
Is there a GPX for the Afon Las from Nant Peris and plateau traverse?
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.