Atlas of Wales

Eryri · Gwynedd · Mountain

Glyder Fawr1,001 m · the highest of the Glyderau

Two ways up to a summit that really is a heap of stone: no railway, no café, just scree and a wide view. What the day asks depends on the line you choose.

Choose your lineChoose your route Is today the day?

The highest of the Glyderau, in Eryri National Park: a shattered-rock summit reached by scree, not a path, with no railway and no café at the top. What the climb asks of you depends on the line, so read the routes before you read the weather.

Height
1,001 m
Ways up
Two · Devil's Kitchen or Pen y Pass
Commitment
A full day from Ogwen; about 2.5 hrs up from Pen y Pass
Terrain
Scree throughout
Exposure & navigation
High on Devil's Kitchen, moderate from Pen y Pass

Choose your lineChoose your route

Two ways up. Only one is yours today.

Devil's Kitchen from Ogwen, or the ridge from Pen y Pass, not interchangeable, and not waymarked. Pick by climb and exposure. The whole board below redraws to your line: its terrain, its shape, its numbers.

Walking routes

Twll Du: the cleft above Cwm Idwal
Your line
1 2 3 4 5 6
  1. 1
    Ogwen Centre car parkThe start: £6/day or £3 for up to 4 hrs, card only. Easiest turn-around.
  2. 2
    Llyn Idwal shoreThe lake path into Cwm Idwal, a National Nature Reserve since 1954: the ground rises through a boulder field ahead.
  3. 3
    Devil's Kitchen "teeth"A steep, narrow passage needing hands and feet on the steepest parts, then a stile at the top. Last easy retreat.
  4. 4
    Llyn y CwnA small alpine lake and a genuine crossroads: a breather before the scree.
  5. 5
    The scree climbSteep and loose for about 300 m. Lines drifting right run close to cliff edges. Keep left.
  6. 6
    1,001 mGlyder Fawr summitA shattered-rock plateau: the summit really is a heap of stone.
1 2 3 4
  1. 1
    Pen y Pass car parkBooking is mandatory via JustPark: no turning up on spec. Easiest turn-around.
  2. 2
    Toward Llyn CwmffynnonRemote, sometimes pathless ground: solid navigation is essential from here.
  3. 3
    The final sectionSteep climbing over loose rock and crags. Last sensible retreat.
  4. 4
    1,001 mGlyder Fawr summitCairned paths meet on the stony plateau; the ridge continues east to Glyder Fach.

Practical brief

Your lineroute in practice ·

The classic Ogwen approach: lake path, then a steep scree finish.

Start point
Ogwen Centre car park, on the A5
Parking / booking
No booking system: card/contactless only, fills quickly at weekends and in spring/summer.
Public transport
TrawsCymru T10 (Bangor–Bethesda–Betws y Coed) and the Bws Ogwen shuttle serve Ogwen; frequency not confirmed. Check Traveline Cymru.
Facilities
Toilets and a snack bar at the Cwm Idwal Centre, Ogwen. Nothing above it.
Return / descent
Back the same way: no alternative descent has been verified for this route. Keep left on the scree both up and down.
Avoid this route if
You're not confident on loose scree, or visibility is poor on the featureless summit boulder field.

A quieter, remoter line: solid navigation required.

Start point
Pen y Pass car park, on the A4086
Parking / booking
Booking is mandatory via JustPark: fills to capacity March–November; not a same-day option if unbooked.
Public transport
Not independently confirmed for this route. Check Traveline Cymru before relying on a bus connection.
Facilities
Not confirmed at Pen y Pass this pass. Do not assume toilets or food are available.
Return / descent
Back the same way: no alternative descent has been verified. The ridge continues east to Glyder Fach for a longer day, if you have the legs.
Avoid this route if
You want a waymarked path: this route crosses remote, sometimes pathless ground.

Route figures: no Eryri National Park-published register exists for Glyder Fawr's summit ascent. Figures are Tier-2 specialist sources, checked 4 August 2026. The Devil's Kitchen figures cover the whole walk from Ogwen; the Pen y Pass figures are to the summit only, so allow for the walk back as well. Parking prices, booking systems and transport change. Confirm current details before you go. Official planning source: Eryri National Park · safety and planning advice

Before you go

Need the exact mountain details?

Parking, transport, toilets, dogs, weather, emergency and descent planning: checked before you go.

Parking & booking

Ogwen (Cwm Idwal) car park

Devil's Kitchen route

Booking
Not required
Price
£6/day · £3 up to 4 hrs

Card/contactless only, no cash. Fills quickly at weekends and in spring/summer; overflow at Bethesda FC, £7/day.

Open parking area Official information

Checked 20 Jul 2026 · Eryri National Park AuthorityParking area verified

Pen y Pass car park

The ridge approach

Booking
Mandatory · JustPark
Address
LL55 4NU
Price
£25 (≤8 hrs) · £35 (8–12 hrs) · £45 (full day)

Blue-badge bays first-come; vehicles over 8 m not accommodated. Booking is mandatory through 1 Nov 2026: this is not a same-day decision.

Open the car park Official information Book parking · JustPark

Checked 20 Jul 2026 · Eryri NPA / JustPark (postcode LL55 4NU, cross-checked against OS grid reference SH 6475 5560)Parking area verified

Nant Peris park & ride

The ridge approach: when Pen y Pass is booked out

Booking
Not required
Price
£5/day

The way onto the ridge without a Pen y Pass booking: park here and ride up. Sherpa’r Wyddfa buses (S1/S2/S5) link to Pen y Pass: 15 min weekends/school holidays, 30 min otherwise. The bus is not a descent plan.

Open parking area Official information

Checked 20 Jul 2026 · Eryri NPA (what3words), cross-checked against independent grid reference SH 607 581Parking area verified

Prices checked 20 July 2026 — the National Park reviews them annually; confirm before you travel via Eryri National Park — Ogwen (opens in a new tab) and Pen y Pass car park (opens in a new tab).

Public transport

The TrawsCymru T10 (opens in a new tab) (Bangor–Bethesda–Betws-y-Coed–Corwen) stops at Llyn Ogwen; Eryri National Park Authority names it as the way in. Partneriaeth Ogwen also runs the Bws Ogwen electric minibus from Bethesda, but it publishes no fixed timetable page. Nothing has been confirmed serving Pen y Pass for this guide. Check the current service before relying on a bus connection to either start point.

Toilets, food & water
  • Ogwen · toilets and a snack bar at the Cwm Idwal Centre, accessible 24 hours.
  • Pen y Pass · not confirmed for this guide. Do not assume toilets or food are available.
  • On the mountain · no toilets, café or shelter on either route between the car park and the summit.
Dogs & livestock

Dogs must be on a lead: a legal requirement on this open-access land between 1 March and 31 July, and sensible practice year-round near livestock. The exact lead length was not confirmed for this guide.

Routes & approach differences

Devil's Kitchen is the shorter, more direct line from Ogwen, up the steep Twll Du cleft and then loose scree to the summit. Pen y Pass is the quieter, remoter approach, crossing ground that's sometimes pathless rather than following a defined line, not an easier alternative, just a different one. Neither is an official National Park route; both are Tier-2 specialist-source figures. Bristly Ridge is not a third route on this page: a specialist mountaineering-guiding source describes it as steep, loose and dangerously eroded, and not recommended as an approach or a descent.

Weather, visibility & winter conditions

The summit plateau is flat and featureless, so cloud turns finding the right line off it into the day's real hazard on either route. Wind picks up hard on the open scree and ridge ground, well past anything felt in the valley, and wet rock makes the Devil's Kitchen scree and the Twll Du cleft considerably harder. No official winter-equipment mandate specific to this mountain was found, but treat any snow or ice as a serious undertaking: an ice axe, crampons and the skill to use them may be needed depending on conditions.

The Met Office publishes a location forecast named for Glyder Fawr (opens in a new tab); MWIS publishes a regional mountain forecast for Eryri/Snowdonia. Read both, and read them as inputs rather than answers: a location forecast does not replace your own judgement about summit wind, cloud, visibility, snow and ice, and neither route has a maintained path or summit shelter to retreat to.

Descent planning & route mistakes

No alternative descent has been verified for either route: reversal is the only confirmed way down. On the Devil's Kitchen scree, keep left both up and down.

Don't treat an alternative ridge descent as a shortcut: Bristly Ridge, for one, is described by a specialist mountaineering-guiding source as steep, loose and dangerously eroded, and not recommended.

Emergency & what not to rely on

Dial 999 or 112 and ask for Police, then Mountain Rescue. Register for emergencySMS in advance so you can text 999 if you can't get a voice signal. Give your location, what's happened, and how many are in your group.

Ogwen Valley Mountain Rescue Organisation (OVMRO) covers this ground, on call 24 hours a day. Neither car park is a rescue plan: Pen y Pass books out in advance, and there is no railway alternative at either start point.

Accessibility & realistic limitations

No step-free or easy route to the summit exists on any source gathered for this guide: honest, not inferred favourably; this is not a first-mountain choice, and not a route for anyone wanting a maintained path. There is no summit facility, shelter, or café on Glyder Fawr, unlike Yr Wyddfa.

Sourced from Eryri National Park Authority, Natural Resources Wales, cwmidwal.cymru, OVMRO and Mountain Rescue England & Wales, checked 14 July 2026.

The reckoning

Now: is today the day?

You have seen the line and the climb; the last question is the weather. Neither route has a maintained path or a summit shelter: in cloud, the summit boulder field is a navigation exercise.

Glyder Fawr forecast (opens in a new tab) MWIS regional forecast (opens in a new tab)

The Met Office link is a location forecast named for Glyder Fawr; MWIS is a regional mountain forecast for Eryri/Snowdonia. Read them together: a location forecast is not a substitute for judging summit wind, cloud, visibility, snow and ice yourself. Valley sunshine does not guarantee a clear summit. Judge the day by the top, not the car park.

  • No summit shelter

    Unlike Yr Wyddfa, there is no building, café or trig shelter at the top: just the open, shattered-rock plateau, exposed to whatever the weather is doing.

  • Scree is worse wet

    Both routes involve loose, steep scree or rock. Rain turns already-loose ground genuinely treacherous, on the way up and — more so — on the way down.

  • The summit plateau is featureless

    The boulder field flattens out at the top with no obvious path. In mist, finding the right line off the summit matters more than the view.

Winter is a different mountain. No official equipment mandate exists for Glyder Fawr specifically, but a specialist mountaineering-guiding source treats the full Glyderau traverse in winter as a serious undertaking requiring an ice axe and crampons.

Good fit for

  • Walkers confident on loose scree and steep, unmaintained ground
  • Parties happy to navigate a featureless summit plateau on their own
  • Anyone wanting a high Glyderau summit without a railway or a café at the top

Think twice if

  • You want a maintained, waymarked path: there is no summit path here
  • This would be a first mountain: neither line is an introduction
  • You need a step-free or easy route to the summit: none exists

The summit

What the climb gives back.

You climb for the view, but the mountain does not always give it. On clear days the panorama opens toward Snowdon and the Carneddau; on cloud days, the rock underfoot is the reward.

The shattered rock plateau of Glyder Fawr under heavy cloud, with a weathered tor on the right and a long mountain ridge on the skyline across the valley
On the summit plateau, Glyder Fawr

On the rightVisible feature

The rock tor

A weathered outcrop standing clear of the boulder field: the "heap of stones" the mountain is named for.

Why it mattersThere is no cairn or trig pillar on Glyder Fawr: the rock itself is the summit marker.

UnderfootGeneral view

The shattered plateau

Frost-broken slabs and loose scree, running flat in every direction with no worn path across them.

Why it mattersThis is the ground that makes cloud the day's real hazard: there is no line to follow off the top.

BelowGeneral view

The lake in the valley

A pale sliver of water far below the plateau, catching what light gets under the cloud. The source names the direction of this view but not the lake, so it stays unnamed here rather than guessed at.

Why it mattersIt gives the drop its scale: the valley floor is the better part of a kilometre below where you are standing.

On the skylineGeneral view

The ridge across the valley

A long, broken skyline on the neighbouring massif, lit under the cloud base: the source names the direction as the Snowdon Horseshoe, but no single peak in this frame can honestly be picked out and named.

Why it mattersIt shows how far the view carries on a half-clear day, and that the Glyderau look across at Snowdon, not up to it.

The way down

Before you leave the summit.

No alternative descent has been verified for either route: reversal is the only confirmed way down. Read the notices, then make the call.

Rocky outcrops and marshy, wintry ground near Llyn y Cwn, on the descent from Glyder Fawr
Summit noticeboard
1

Navigation on the summit

The boulder-field plateau is featureless in mist: even experienced walkers lose the line.

  • Fix the descent line before you leave the summit.
  • Carry a map and compass. Do not rely on a phone alone.
  • If unsure, stop and re-check.
Common mistake
2

Fading light

There's no shortcut down and no shortcut back. Do not get caught out.

  • Turn around early enough to avoid a late finish.
  • Keep headtorches ready.
  • Plan for slower progress than you expect.
Turn back early
3

Scree fatigue

Loose scree is harder on tired legs: the Twll Du line especially.

  • Keep left on the scree, both up and down.
  • Take a proper break before descending.
  • Watch for lagging or unsteady people.
Know your limits
4

Don't treat a shortcut as easier

Pen y Pass books out in advance, and there's no railway at either start point.

  • An alternative ridge descent (e.g. Bristly Ridge) is steep, loose and eroded, not recommended.
  • Do not rely on signal, luck, buses or a car park space.
  • Self-reliance keeps the group safe.
Plan, don't rely

Back in the valley.

The mountain casts a long day. These are the places around it.

Yr Wyddfa's summit in cloud above Llyn Llydaw
Mountain

Yr Wyddfa

The highest mountain in Wales: six routes, one scramble, and a summit railway. A different kind of mountain day.

Read the guide →
Moel Siabod turned red by an early-morning winter sun
Mountain

Moel Siabod

A quieter Eryri summit near Capel Curig, along the same A5 corridor as Ogwen.

Read the guide →
The summit of Y Garn, with Llyn Ogwen and Llyn Idwal below and Tryfan beyond
Mountain

Y Garn

The next top along the same ridge: a walked 947m summit on the Ogwen circuit, without this one’s scree.

Read the guide →
Llyn Idwal's still water reflecting the cliff line of Cwm Idwal, Eryri
Nature reserve

Cwm Idwal

The cwm directly below, where the Devil’s Kitchen route starts: Wales’ first National Nature Reserve, and a lake circuit if the tops are out.

Read the guide →

On the Atlas

Continue from Glyder Fawr.

The highest of the Glyderau, above the Ogwen valley.

Open Glyder Fawr on the map

Continue exploring

The last boulders fall behind.Glyder Fawr remains raw and open.

Take that high, broken landscape into the wider Glyderau.

Open Glyder Fawr on the map Open Gwynedd Atlas