Brecon Beacons

The Brecon Beacons National Park 357283 357283 is a National Park in the United Kingdom.

Sources

Because the national park was created after the publication of the NPE, there are no map sources for the boundary. An explanation of the boundary added to OSM follows below. The boundary as represented in OSM is a rough boundary only and cannot be regarded as a complete or accurate boundary. Other people who know the Brecon Beacons National Park are encouraged to edit the boundary if they think it is wrong.

Boundary so far

• The Monmouthshire & Brecon Canal extends to Pontypool through the National Park for virtually all it's length. The National Park also ends near Pontypool so this canal has been used as part of the boundary until Abergavenny.
• Abergavenny is unlikely to be inside the National Park
• The Black Mountains, to the north of the town, are definitely part of the National Park. Skirting the town using waterways where possible as this is likely to be what the real boundary does.
• The Skirrid is definitely in the National Park and Wikipedia confirms this.
• Llanvihangel Crucorney on Wikipedia is apparently inside the National Park, articles for other nearby villages do not say or say 'near'.
• Using Welsh National Boundary north of Llanvihangel Crucorney to Haye-on-Wye.
• Hay on Wye on Wikipedia is within the National Park according to Wikipedia.
• Llanigon on Wikipedia is described as being on the edge of the national park while Glasbury on Wikipedia is described as being just outside the national park.
• The Afon Llynfi on Wikipedia runs close to these villages and the town of Talgarth and is described as forming part of the national park boundary.
• Brecon itself is either within or very close to the National Park boundary. I've put the boundary along the A40, excluding the town for now. I don't know if this is correct but I would imagine that a major road like the A40 would be excluded from the National Park especially when it was so close to the edge of the park anyway.
• Following A40 to Llandovery.
• According to Llandovery on Wikipedia the town is not inside the national park but that the nearby village of Myddfai is.
• Unsure where the boundary goes from Llandovery but it does go to Lladeilo so have put it on the Heart of Wales line to Llandeilo.
• Trap on Wikipedia states that this village is on the National Park boundary.
• Brynamman on Wikipedia is immediately south of the main part of the Black Mountain on Wikipedia so the boundary must either include or exclude this village but will be in the immediate vicinity.
• Abercraf on Wikipedia is apparently just outside the National Park boundary.
• Coelbren on Wikipedia is described as being within the National Park.
• The Afon Pyrddin on Wikipedia is described as forming part of the National Park Boundary. It also forms existing county boundaries in OSM, so will use this south of Coelbren.
• Pontneddfechan and the Afon Mellte on Wikipedia are both apparently inside the National Park
• Hirwaun on Wikipedia is described as being just outside the boundary. Using railway and A465 to conveniently skirt the town.
• Aberdare and Merthyr are definitely outside the national park.
• Using Powys County boundary to Trefil
• Trefil on Wikipedia is apparently one mile south of the boundary, which would fit with the county boundary theory
• Brynmawr is not in the National Park, IIRC. Skirting it using a stream and old railway.
• The Blorenge on Wikipedia is inside the national park.
• Blaenavon isn't.
• With little to go on as to where the boundary might lie, I've just drawn a temporary line around Blaenavon and to the river. I've used the river to Pontypool where it meets to Monmouthshire & Brecon canal again.

Final section

The final section added around Blaenavon to Pontypool is complete guesswork based on where the boundary starts at the Monmouthshire & Brecon canal. This section urgently needs attention by someone who knows the Brecon Beacons National Park in the immediate area around Blaenavon and Pontypool.