Pen-y-Gwryd via Llyn y Caseg Fraith up Gallt yr Ogof: route map, distance and time
763 m · Snowdonia
A hard mountain walk to the summit from Pen-y-Gwryd public path.
Pen-y-Gwryd via Llyn y Caseg Fraith starts at about 278 m and gains 538 m over 4.5 km to 741 m on the track. It is steep from the start: the first kilometre climbs 183 m (18%). The steepest kilometre is the one ending at 2 km, which climbs 226 m at an average of 23%, with a 500 m stretch from 0.6 km at about 31%. The final 0.5 km eases to the top. About 30% of the way is steeper than 1 in 5, so expect hands-on-knees going and a slow descent.
Pen-y-Gwryd via Llyn y Caseg Fraith at a glance
| Distance | 4.5 km one way, to the top |
|---|---|
| Ascent | 570 m |
| Climb on the track | 538 m up, 76 m down on the way |
| Start and top of the track | 278 m to 792 m (summit 763 m) |
| Steepest 500 m | About 31%, from 0.6 km |
| Steeper than 1 in 5 | 30% of the way |
| Time up | 1h 50m by Naismith's rule |
| There and back | 2h 45m, down the same way |
| Grade | Hard |
| Start | Pen-y-Gwryd public path |
| Start grid reference | SH 661 559 |
| Summit grid reference | SH 685 585 |
| Parking | No checked car park for this start; find lawful parking nearby |
Pen-y-Gwryd via Llyn y Caseg Fraith 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 Pen-y-Gwryd via Llyn y Caseg Fraith 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.
Pen-y-Gwryd via Llyn y Caseg Fraith 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 | 461 m | +183 m | 18% | SH 662 567 |
| 2 km | 688 m | +226 m | 23% steep | SH 667 575 |
| 3 km | 741 m | +53 m | 5% | SH 672 582 |
| 4 km | 718 m | -23 m | -2% | SH 681 583 |
| 4.5 km | 741 m | +23 m | 5% | SH 685 585 |
How long Pen-y-Gwryd via Llyn y Caseg Fraith takes
| Pace | To the top | There and back |
|---|---|---|
| Brisk 6 km/h, 8 min per 100 m up | 1h 30m | 2h 15m |
| Steady (Naismith) 5 km/h, 10 min per 100 m up | 1h 50m | 2h 45m |
| Relaxed 4 km/h, 12 min per 100 m up | 2h 15m | 3h 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 07:49, sunset 18:11. Start by 14:26 to be down before dark, allowing 2h 45m for the walk and an hour for stops.
- Tomorrow: sunrise 07:51, sunset 18:09. Start by 14:24 to be down before dark, allowing 2h 45m for the walk and an hour for stops.
Gallt yr Ogof summit weather for this route
There is no recent summit forecast cached for Gallt yr Ogof right now. The main Gallt yr Ogof page loads the live forecast when you open it. Open the live Gallt yr Ogof forecast.
Before you go, also check: MWIS Snowdonia forecast · Met Office mountain forecast.
About Gallt yr Ogof
More about Gallt yr Ogof, with the live forecast.
Challenges that include Gallt yr Ogof
More walks from Pen-y-Gwryd public path
Routes in Peakify's guides that start within 500 m of this one, for another day from the same car park.
- Pen y Gwryd via the Miners' Track up Glyder Fach
- Miners' Track from Pen-y-Gwryd and plateau traverse up Glyder Fawr
- Western approach from Pen-y-Gwryd up Moel Siabod
- Pen-y-Gwryd via Llyn y Caseg Fraith up Y Foel Goch
Other routes up Gallt yr Ogof
| Route | Distance | Ascent | Time up | Grade |
|---|---|---|---|---|
| Eastern Glyderau from Capel Curig | 4.7 km one way | 590 m | 1h 55m | Hard |
In an emergency
Call 999, ask for the police and then mountain rescue. Give your location (the start is at SH 661 559, the summit at SH 685 585), 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.
Pen-y-Gwryd via Llyn y Caseg Fraith: questions and answers
How far is Pen-y-Gwryd via Llyn y Caseg Fraith?
Pen-y-Gwryd via Llyn y Caseg Fraith is 4.5 km one way to the summit of Gallt yr Ogof, with 570 m of ascent. There and back by the same way is about 9.0 km.
How long does Pen-y-Gwryd via Llyn y Caseg Fraith take?
About 1h 50m to the summit of Gallt yr Ogof and 2h 45m 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 3h 25m for the round trip.
How steep is Pen-y-Gwryd via Llyn y Caseg Fraith?
The steepest 500 m averages about 31%, starting 0.6 km from the start, and 30% of the way is steeper than 1 in 5. Pen-y-Gwryd via Llyn y Caseg Fraith climbs 538 m in all on the track.
Where do you park for Pen-y-Gwryd via Llyn y Caseg Fraith?
Pen-y-Gwryd via Llyn y Caseg Fraith starts from Pen-y-Gwryd public path. The grid reference is SH 661 559. No checked car park for this start; find lawful parking nearby
Is Pen-y-Gwryd via Llyn y Caseg Fraith 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 Pen-y-Gwryd via Llyn y Caseg Fraith today?
By 14:26 at the latest. Sunset on Gallt yr Ogof today is 18:11, Pen-y-Gwryd via Llyn y Caseg Fraith takes about 2h 45m there and back, and that leaves an hour for stops. Start earlier in winter or if the forecast turns.
Is there a GPX for Pen-y-Gwryd via Llyn y Caseg Fraith?
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.