Craig Cerrig Gleisiad a Fan Frynych National Nature Reserve, near Brecon

Craggy mountain landscape in the Brecon Beacons National Park

What's here

This site and visitor facilities are open – please see more details on this web page.


Coronavirus update


The Welsh Government is implementing a national coronavirus firebreak from 6pm on Friday 23 October until Monday 9 November.


The firebreak regulations replace the local restrictions which were in force in some parts of the country. They apply to everyone living or travelling in Wales.


Our sites and most visitor facilities remain open during this firebreak period but people are advised to stay at home and only visit sites in the local area to take exercise.


Visiting your local site safely


We have changed the normal route for some of our trails to help you maintain social distancing – please follow signs on site.


You need to wear a mask when going inside one of our buildings.


You can check-in via the NHS app when entering one of our buildings – scan the QR-code on the NHS Covid-19 poster on site.



Just a few hundred metres from the busy A470, you will find yourself enclosed within a shady, atmospheric amphitheatre created by the soaring, craggy cliffs of Craig Cerrig Gleisiad.

Try our waymarked walks to get a flavour of the reserve or, for map-readers wanting a longer walk, footpaths lead upwards to the lofty, exposed moorlands of Fan Frynych and across to the spectacular cliffs at Craig Cwm Du.

There is a picnic site next to the reserve entrance.

Toilets and a café are a short drive away at the Brecon Beacon’s National Park Visitor Centre in Libanus and in the car park opposite the Storey Arms outdoor education centre.

Walking trails

The walking trails are waymarked from start to finish.

Look out for the information panel at the start of the trails.

Find out about walking trail grades.

Under the Cliff Walk

  • Grade: moderate
  • Distance: 1½ miles/2.5 kilometres (there and back)
  • Total climb: 400 feet/120 metres
  • Time: 1 hour
  • Trail information: The trail follows an uneven and increasingly steep narrow path and returns along the same route. The reserve is grazed by cattle, sheep and mountain ponies - please keep dogs under close control.

Experience the majestic landscape on this walk along the river to the base of the rocky slopes of Craig Cerrig Gleisiad.

Bluestone Walk

  • Grade: difficult
  • Distance: 2¼ miles/3.5 kilometres
  • Total climb: 860 feet/260 metres
  • Time: 1½ hours
  • Trail information: The trail follows an uneven and increasingly steep narrow path over uneven ground with loose stones. It returns down a steep, grassy slope and has stepping stones to cross a stream. The reserve is grazed by cattle, sheep and mountain ponies - please keep dogs under close control.

You get a great feel for the craggy heights of Craig Cerrig Gleisiad from both near and far on this circular route.

It sets off alongside the river and climbs steeply through heather and bilberry to a cairn.

There are great views towards Pen y Fan on the return.

Other walking routes

There are footpaths leading upwards to the plateau of Fan Frynych and across to Craig Cwm Du.

These may not be signposted and we recommend that you take a map with you.

The Beacons Way

The Beacons Way goes along the edge of the reserve’s boundary.

This 99 mile (159 kilometre) long-distance route involves remote and rugged terrain and has limited waymarking, especially on open hill and moorland sections.

The route is shown on the Ordnance Survey (OS) map or you can get a route guide from the Brecon Beacons National Park's online shop.

For more information about the Beacons Way go to the Brecon Beacons National Park website.

What to see at the National Nature Reserve

Dramatic landscape created by glaciers

A glacier carved out this valley during the last ice age.

As it melted, about 18,000 years ago, it exposed the steep rock walls of Craig Cerrig Gleisiad.

Some time later, a catastrophic landslide cascaded millions of tonnes of rock from these crags down the slopes.

Archaeological remains found on the reserve show that the area has been inhabited for many thousands of years.

Apart from Iron Age huts there are also the remains of a Roman road and later farm settlements.

Rich variety of plantlife

The steep rocky slopes, sharp escarpments and crags are home to rare arctic-alpine plants. These are at their southernmost location in the UK and are not found again until the Alps.

Arctic-alpine wildflowers grow on the north-facing rocky cliffs. They include purple saxifrage, mossy saxifrage, serrated wintergreen and green spleenwort.

The cliffs are, in effect, a vertical woodland with trees and shrubs of hawthorn, rowan, ash and rare whitebeams.

There is a also rich variety of wildflowers and many different mosses and liverworts.

Seasonal highlights

Early spring to mid-summer is a great time to see the reserve’s spectacular range of wildflowers and also its birdlife including peregrines, kestrels, red grouse and rare ring ouzels.

In August and September the hillsides come alive with the glow of heather.

National Nature Reserves in Wales

There are over 70 National Nature Reserves in Wales.

National Nature Reserves are places with some of the very finest examples of wildlife habitats and geological features.

Find out more about National Nature Reserves.

Brecon Beacons National Park

Craig Cerrig Gleisiad a Fan Frynych National Nature Reserve is situated in the Brecon Beacons National Park.

The National Park covers approximately 520 square miles of mountains and moorland in South and Mid Wales.

For more information about visiting the Brecon Beacons go to the Brecon Beacons National Park website.

How to get here


Craig Cerrig Gleisiad a Fan Frynych National Nature Reserve is approximately seven miles south of Brecon.

It is in the county of Powys.

Ordnance Survey map

Craig Cerrig Gleisiad a Fan Frynych National Nature Reserve is on Ordnance Survey (OS) map OL 12.

The OS grid reference is SN 971 222.


The best starting point to visit the reserve is a large lay-by adjacent to the A470, approximately seven miles south of Brecon – look out for the information panel just beyond the gate at the reserve entrance.

From Brecon: Follow the A470 towards Merthyr Tydfil and the layby is on the right, immediately after passing a youth hostel on the left.

From Merthyr Tydfil: Follow the A470 towards Brecon and the lay-by is on the left, two miles north of the Storey Arms outdoor activity centre.

Public transport

Buses on the Merthyr Tydfil to Brecon route stop on the A470, near the reserve entrance.

For details of public transport visit the Traveline Cymru website.


There is a large lay-by adjacent to the entrance to the reserve - look out for the reserve sign just behind the gate.

Closures and diversions

  • Sometimes we need to close or divert trails for your safety whilst we undertake maintenance work or other operations.
  • We may have to close a site in extreme weather, such as high winds or snow and ice, due to the risk of injury to visitors or staff.
  • Please always follow any instructions on site and any temporary diversion signs.

Contact us

0300 065 3000

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