SH6529 : Feral goats on Rhinog Fawr
Hard mountain walking; navigation and scrambling

Rhinog Fawr

721m Elevation
367m Prominence
Wales Country
Find walking friends Explore routes

Good walks are even better shared.

SH6529 : Feral goats on Rhinog Fawr

Peter S Photo source

Overview

Rhinog Fawr is a 721 m mountain in the Rhinogydd of Eryri, Gwynedd. Rocky terraces, deep heather and intermittent paths make it a demanding hill despite its modest height. Summit walks approach from Cwm Bychan via the Roman Steps or from Cwrt Forest near Graigddu-isaf.

Rhinog Fawr

Rhinog Fawr rises to 721 m (2,365 ft) in the Rhinogydd of Eryri, Gwynedd. It is a Marilyn, Simm, Hewitt and Nuttall with 367 m prominence. Its relatively modest height disguises a demanding mountain of rock terraces, heather and fragmented paths.

Summit and landscape

The recorded high point is a rock 8 m west of the cairn. The rock beside the trig point, 25 m farther west, is about 1 m lower. These distinctions follow the Database of British and Irish Hills v18.6 record, revised 11 December 2025. Nearby Rhinog Fach is 711.6 m and Y Llethr is 755.1 m; the deep Bwlch Drws Ardudwy separates Fawr from Fach.

The mountain's hard Cambrian sandstone of the Rhinog Formation, often called grit or greywacke, began as sediment deposited by underwater flows. Glacial erosion later shaped the passes and rock surfaces. Most of Fawr lies in the Rhinog National Nature Reserve. Heather, bilberry, boulders and cliffs give it a notably wild character; flowering heather colours the reserve in July and August.

Choosing a route

The most direct Cwm Bychan option uses the Roman Steps to Bwlch Tyddiad, then Llyn Du and the steep upper mountain, returning the same way. UKHillwalking lists 7.75 km, 570 m ascent and 3–4 hours. A Gloyw Lyn circuit adds a much harder navigation problem on the descent. The route cards distinguish this from the longer eastern circuit via Bwlch Drws Ardudwy, the approach from Cwrt Forest and the long northern-tarns circuit. Their distances and times belong to those specific complete itineraries, not to interchangeable summit approaches.

Roman Steps is the name of a medieval packhorse trail. It crosses Bwlch Tyddiad north of the summit. Bwlch Drws Ardudwy is the separate pass south of Fawr, between Fawr and Fach. The name Rhinog Fawr is commonly translated as Big Threshold.

Terrain and safety

Beyond the approach paths, expect steep broken ground, loose scree, wet slabs, heather-covered rocks and short sections requiring hands. Paths can vanish on rock or among vegetation. In mist, a line that initially looks promising can lead towards crags; choose a documented descent and be prepared to retrace your route. The Gloyw Lyn descent and northern tarns circuit particularly demand experienced navigation.

Carry a large-scale map and compass and know how to use them, with mountain footwear, waterproofs and warm layers. Wet or icy rock increases the difficulty; snow can conceal the irregular ground. Natural Resources Wales warns that Llyn Du is deep: keep out of the water. Follow any forestry closure or diversion signs.

Access

Cwm Bychan has a paid car park/campsite at the end of the narrow lane from Llanbedr, around SH645315. No public transport reaches this start; rail or bus travel to Llanbedr or Harlech needs a separately planned onward journey.

For the eastern approach, use Cwrt Forest car park near Graigddu-isaf, SH684302. NRW lists free parking and prohibits overnight parking. Its gated approach road leaves a fast section of the A470; use the official directions and leave gates as found. Bring food and drink for the mountain day.

References

Explore routes near Rhinog Fawr

Walks starting near this hill. Open a route to check its map, distance and full itinerary.

Northern Rhinogydd guided mountain walk

View route

Coed y Brenin: Pont Ty'n-y-groes and Mawddach Forest Trail

10.7 km ~4h Moderate

View route

Mawddach Trail: Penmaenpool to Arthog Estuary Return

14.7 km ~4h 15m Easy

View route

Mawddach Trail: Penmaenpool to Dolgellau Riverside Return

7.3 km ~2h 30m Easy

View route

Route planning notes

These notes describe possible approaches. Check a route's map and access information when planning your walk.

Roman Steps and Llyn Du from Cwm Bychan (return)

Start and finish at Cwm Bychan car park/campsite (SH645315), reached from Llanbedr. Follow the Roman Steps to Bwlch Tyddiad, then the rough side path south to Llyn Du and one of the steep north/northwest summit trails. Retrace the ascent to Cwm Bychan. UKHillwalking gives approximately 7.75 km, 570 m ascent and 3–4 hours for the full return. Its Moderate grade includes intermittent rocky upper paths and hands-on steps; confident navigation and sure footing are needed.

7.8 km Hard mountain walking

Rhinog Fawr and Gloyw Lyn from Cwm Bychan

Circular from Cwm Bychan car park (SH645314): Roman Steps and Bwlch Tyddiad, Llyn Du northern shore, then the wall and short scrambling gully to the summit. Descend southwest to the wall, then northwest through rough ground to Gloyw Lyn. Follow its western shore, then turn northeast to regain the outward path and the car park; the northbound path beyond the lake enters the wrong valley. Walking Britain gives about 8.1 km, 585 m ascent and 4 hours 10 minutes. The confusing descent is unsuitable for inexperienced walkers or poor visibility.

8.1 km Moderate/Hard; difficult navigation

Rhinog Fawr from Cwrt Forest / Graigddu-isaf

Start and finish at the Cwrt Forest car park near Graigddu-isaf (official grid SH684302). Follow forest paths past Pistyll Gwyn towards Bwlch Tyddiad, branch to Llyn Du and climb the rough northern gully to the summit. Return southwest to the western wall, descend to Llyn Du, cross its northern shore, and rejoin the forest approach. Mud and Routes gives about 9.82 km, 582 m ascent and 5 hours for its circuit, including the higher wet return contour towards Bwlch Tyddiad. Its parking point is slightly farther southwest. Loose rock, damp slabs and short scrambles make progress slow.

9.8 km ~5 hours Hard; scrambling and navigation

Roman Steps and Bwlch Drws Ardudwy circuit

Start and finish at Cwm Bychan (SH646315). Climb the Roman Steps, turn towards Llyn Du and use its east/south shores and western summit approach. Descend east, then south towards Bwlch Drws Ardudwy; take the northeast forest-edge path to Pistyll Gwyn, then climb west over Bwlch Tyddiad and descend the Roman Steps to Cwm Bychan. The Great Outdoors gives about 11.7 km, 766 m ascent and 5 hours. The steep descent has intermittent paths among heather and rocks and a wall crossing; this is a more committing circuit than retracing the ascent.

11.7 km ~5 hours Hard; steep, faint-path descent

Bwlch Gwilym, northern tarns and Rhinog Fawr

Circular from and back to Cwm Bychan. Head north to Bwlch Gwilym, then via Llyn Twr-glas, the east shore of Llyn Pryfed, scrambling gullies and rough tops above Llyn Morwynion to Bwlch Tyddiad. Climb past Llyn Du and the western shoulder to Rhinog Fawr. Return to Llyn Du and Bwlch Tyddiad, then descend the Roman Steps to the starting car park. Mud and Routes gives about 13.46 km, 838 m ascent and 7 hours. Faint paths, repeated scrambles and difficult route-finding make this a long expert-navigation day.

13.5 km ~7 hours Hard; complex navigation and scrambling
Browse more walks on the map

Make a day of it, together

Find someone to share the walk with, or organise a day out along a route you like.

Find walking friends Plan a walk here
Hill facts and local notes

Classifications

Marilyn Simm Hewitt Nuttall

Elevation

721m

2,365 ft

Prominence

367m

Coordinates

52.8418, -3.9954

SH657290

OS Map

124

Explorer: OL18W

At the Summit

The highest point is a rock 8 m west of the cairn, at SH657290 (detailed reference SH 65700 29013). DoBIH records the rock beside the trig point, 25 m west at SH 65673 29010, as 1 m lower.

Terrain & Geology

Rock terraces and boulder fields deep heather and bilberry intermittent mountain paths loose scree and short scrambles boggy hollows woodland paths and stone-laid Roman Steps

Hard sedimentary rocks of the Cambrian Rhinog Formation, including thick-bedded sandstone (greywacke or grit) with finer beds, form the craggy mountain. These sediments accumulated through underwater flows in a submarine-fan setting. Later ice erosion shaped the passes, valleys and scoured rock surfaces.

Views & Scenery

In clear weather, views include nearby Rhinog Fach and Y Llethr with Llyn Hywel between them, the Meirionnydd coast and the Llŷn Peninsula. Llyn Du lies beneath the summit crags.

Best Seasons

Heather flowers colour the nature reserve in July and August. Summer visitors may also see wheatears, meadow pipits and ring ouzels.

History & Heritage

Name Origin

Commonly translated as “Big Threshold”: Rhinog refers to a threshold, and fawr means big.

Historical Significance

The Roman Steps at Bwlch Tyddiad are a medieval packhorse trail, despite their popular name. They formed part of an old route through the mountains. The distinct Bwlch Drws Ardudwy pass between Rhinog Fawr and Rhinog Fach also linked the coast with inland country.

Getting There & Facilities

Parking

Cwm Bychan paid car park/campsite at the road end near SH645315, reached along the narrow lane from Llanbedr. For the eastern approach, Cwrt Forest car park near Graigddu-isaf is at SH684302: NRW lists free parking and no overnight parking. The gated approach leaves a fast section of the A470; follow NRW directions, leave gates as found and obey any forestry closures or diversions.

Public Transport

No public transport reaches the Cwm Bychan walk start. Rail or bus travel to Llanbedr or Harlech needs a separately planned onward journey along the long approach lane; arrange transport rather than assuming a connecting service.

Nearby Facilities

Bring food and drink for the mountain day. Cwm Bychan offers paid parking/camping; do not rely on older reports of a portaloo. Cwrt Forest has parking and trail information, with no staff on site. Harlech, Llanbedr and Trawsfynydd are bases for supplies away from the summit routes.

Safety Information

Known Hazards

  • Steep slopes, cliffs, loose scree and short scrambling sections; wet slabs and heather-covered rocks can be slippery.
  • Upper paths are intermittent. Complex terraces and crags make navigation and descent difficult in poor visibility; carry a map and compass and allow time for slow progress.
  • The Gloyw Lyn descent and northern-tarns circuit have particularly confusing route-finding; the northbound path beyond Gloyw Lyn leads into the wrong valley.
  • Llyn Du has deep water: Natural Resources Wales advises keeping out.
  • Cwrt Forest access turns off a fast section of the A470. Follow official directions and forestry closure or diversion signs.

Seasonal Hazards

Rain makes slabs, heather and boggy ground slippery. Snow can conceal boulders and holes, while ice increases the difficulty of scrambles and the stone-laid paths. Winter conditions require suitable equipment and skills; short daylight leaves less margin for slow route-finding.

General Safety Tips

  • Check weather conditions before setting out
  • Carry appropriate clothing and equipment
  • Let someone know your planned route
  • Take a map, compass, and GPS device
  • Carry emergency supplies: food, water, first aid kit, torch

Hills

Some common questions about the hills answered

Are there group walks up Rhinog Fawr?

Many walkers use Walkmates to join or organise walks with others. You can check for group walks around Rhinog Fawr through the maps

Are there other walkers around Rhinog Fawr?

Activity varies by location and time, but Walkmates lets you see whether others have shared walks or shown interest in this area. Find other people through the walking friends search walking friends for Rhinog Fawr search or of course create your own walk for Rhinog Fawr

Can I organise a walk to Rhinog Fawr?

Yes. If there aren’t any walks listed already, you can create a walk and make it available for others to join.

If you're signed up to Walkmates, you can create a walk to Rhinog Fawr.

How do I find a walk up this hill?

There are often multiple ways to walk this hill, depending on experience and route preference. Walkmates helps you explore walks and routes that others have shared.

Can I suggest a new route up Rhinog Fawr?

Yes. You can suggest or create routes to share with others. Walkmates focuses on the social side of walking, so routes are used to help people organise walks and explore areas together, rather than as detailed navigation tools or route libraries.

Other uses really appreciate knowledgeable walkers sharing their routes. Share your favourite route to Rhinog Fawr here

The is an error or something incorrect about this hill. How do I let you know?

We always strive to keep the information on Walkmates as accurate as possible. If you find an error, please let us know through the contact form and we'll aim to correct it as quickly as possible

Location

Rhinog Fawr location map

Grid reference: SH657290

View on OpenStreetMap

Opens a map in a new tab, centred on the hill.

Nearby Hills

Y Garn

629m

Moelwyn Mawr

770m

Cnicht

691m

Cadair Idris - Penygadair

893m

Moel Hebog

784m
See 5 more nearby hills