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Exploring Pen y Fan and Corn Du

A landscape shot looking across the green peaks of Brecon Beacons National Park, Powys.
Peaks in the Brecon Beacons National Park | © National Trust Images/Paul Harris

Pen y Fan and Corn Du, the two highest peaks of the central Brecon Beacons dominate the landscape for miles around. It has become one of the most recognisable skylines in the UK and green Valleys surround the peaks. Go exploring and discover hidden lakes and ancient woodlands along the way.

Pen y Fan

At 886m, Pen y Fan is the highest mountain in southern Britain, followed by Corn Du at 873m and Cribyn at 795m, and each year more than 250,000 pairs of feet make the trek to the summits of these impressive peaks.

An exhilarating landscape

The landscape is high, remote and exhilarating. The long ascent to the top of Pen y Fan is well worth the effort for views stretching across south and mid-Wales, the Severn Estuary into South-West England. On a clear day, the Cambrian Mountains, Black Mountains, Gower, Herefordshire, Gloucestershire and Somerset are also visible.

A hidden lake

If you look north west from Corn Du or Pen y Fan, just where the steep slopes start to fall away, Llyn Cwm Llwch captures the eye.

Llyn Cwm Llwch is the best preserved glacial lake in South Wales and sits at the head of the Cwm Llwch valley . This forms part of the Bannau Brycheiniog Site of Special Scientific Interest (SSSI) and is also a Geological Conservation Review (GCR) site.

A view of walkers on a steep hillside on the Cwm Llwch horseshoe trail, Brecon Beacons, Powys, with rolling hills and woodland in the far distance.
Walkers on the Cwm Llwch horseshoe trail, Brecon Beacons | © National Trust Images/John Millar

Cwm Gwdi

Cwm Gwdi is the place to start some of the most spectacular and toughest walking in the Bannau Brycheiniog (Brecon Beacons), South Wales, and is full of history.

A valley training camp

Cwm Gwdi was once a military training camp dating back to Victorian times. The concrete bases of the abandoned buildings can still be seen amongst the trees.

The army once used the hill Allt Ddu, on the east side of the valley, for mortar practice. The army continued to use the camp for hill walking until 1996 when it was taken into the care of the National Trust.

Upper Tarell Valley and ancient woodland

Surrounded by the wild, open mountains of the Bannau Brycheiniog , the Upper Tarell Valley is home to some of our few remaining semi-ancient woodlands. Coed Carno and Coed Herbert are the two main woods in the Tarell Valley which are semi-ancient woodlands. They have grown naturally on undisturbed soils over hundreds of years.

Phoenix trees

One of the wonders of Coed Carno and Coed Herbert are the phoenix trees. These trees have fallen yet they continue to grow. They bring the rich green canopy of the woodland down to ground level.

Redstart in flight at Barton Wood, Devon
A red start in flight | © National Trust Images / Joshua Day

Flora and fauna to see in the Brecon Beacons

Look out for a variety of woodland birds including pied flycatchers, wood warblers, redstart and chiff chaff. Redwings and flocks of fieldfares can often be seen flying over the fields surrounding the woods.

Plant life can grow undisturbed and features bluebells, wood anemone, red campion, lesser celandine along with rare fungi and lichen.

River Tarrell residents

The River Tarell provides a wild environment for otters and a variety of freshwater dippers. These playful creatures and birds can often be seen enjoying the remote and tranquil space.

View from Pen y Fan to Corn Du in the Brecon Beacons National Park, South Wales.

Discover more at the Brecon Beacons

Find out how to get to the Brecon Beacons, where to park, the things to see and do and more.

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