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Walk This May: National Park Staff recommended routes


National Walking Month
This week’s walk recommendation is Penwyllt by Alan Bowring, Geopark Development Officer, Fforest Fawr UNESCO Global Geopark.

Alan Bowring

We’ve had a lot of time in recent months to dream where we might want to explore when that simple freedom was permitted once again. Did you, like me, pore idly over maps or scan aerial images of hills and coasts, imagining yourself there? Perhaps an odd feature caught your eye, left you wondering? If you happened to scroll your way across the Brecon Beacons, you might have chanced upon a curious corner of the National Park which also goes by a curious name.

This is Penwyllt – it’s sometimes translated as the ‘end/edge of the wild’. Zoom into aerial photos of the place and you’ll see why this former village deserved its name.

Do you see swirls and swirls of grey, set in a green ‘sea’? Do you see lines, some broad, some narrow, some grey, some green, criss-crossing this landscape? Do you see a pock-marked surface – holes, large and small? Do you see a scatter of buildings, some roofed, others ruinous?

Penwyllt by Neil Mansfield
© Neil Mansfield

What you can see is a ‘palimpsest’. This wonderful word originally meant a material such as parchment or a tablet on which things are written, then erased, time and again. Reading the latest message you can always find traces of the earlier ones. Penwyllt and its hinterland is the landscape equivalent; lines and layers in today’s landscape overlie earlier features which are laid across even earlier ones and so on.

© Neil Mansfield
© Neil Mansfield

Those swirls are cracked and angled layers of limestone and gritstone from the Carboniferous period. At over 300 million years ago, that’ll be the oldest layer in this palimpsest! Many of the grey areas are rock pavements, some limestone, some gritstone, most of them within the Ogof Ffynnon Ddu National Nature Reserve. Wonderful as its limestone pavements are, you don’t get to see all the best bits of the reserve in these aerial shots as many are are underground; ‘OFD’ as cavers call it is Britain’s deepest cave (274.5m) and one of its longest (over 50km). But follow one of those straggly green lines – it happens to be the Beacons Way – and you’re effectively tracing out the route of the cave. Many of the pockmarks are connections of a sort between our sunlit world and that nether world, these are shakeholes and there are a lot of them here, big and small. Others are one-time quarries associated with the fire-brick works, the remains of which bear witness to decades of industry in this now isolated and peaceful place.  And various of the remaining lines will be found to be old railways, tramroads or inclines – great walking routes to traverse an otherwise rough landscape.

The most recent details to be overlaid have a smaller footprint on the landscape. A leaflet – ‘Penwyllt Geotrail’ – describes a circular walk through this place from Craig-y-nos Country Park down in the valley. Unwrap the story of this place and delve into its history and deep prehistory.

Download the Penwyllt Geotrail here or pick one up from Craig-y-nos Country Park or the National Park Visitor Centre.

When out walking please remember to follow Welsh Government Social distancing rules and visit the Brecon Beacons National Park safely.



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