Black Mountain South Top

The Black Mountain (Welsh: Twyn Llech), is a mountain in the Black Mountains. It is the only Marilyn to fall exactly on the Welsh–English border, Powys and Herefordshire. Its parent peak, Waun Fach, lies to the west.

Hay Bluff (Welsh: Penybegwn) is a prominent hill at the northern tip of the Black Mountains, an extensive upland massif which straddles the border between south-east Wales and England. The mountain sits at the point where the main northeast-facing escarpment of the Black Mountains meets the northwest facing escarpment, the next peak to the west being Twmpa. The flat summit of Hay Bluff which is marked by a triangulation pillar at a height of 677 metres (2,221 ft) overlooks the middle Wye Valley and the book town of Hay-on-Wye. The hill is largely within the Welsh county of Powys though parts of its eastern flanks lie within the English county of Herefordshire.

The Black Hill (also known as Crib y Garth) is a hill (elevation 2100 feet or 640m) in the Black Mountains in Herefordshire, England at grid reference SO275348. It rises just west of the village of Craswall, near the border with Wales. The southern part of the ridge leading to the summit is a rocky knife-edge giving excellent views to either side. The northern part crosses a peat bog on gently sloping land at the edge of the east facing escarpment. The lower part is very similar to the main ridge of the Skirrid mountain near Abergavenny, owing to their similar underlying geology. The Black Hill is known locally as the 'Cat's Back,' as viewed from Herefordshire it looks like a crouching cat about to pounce.

The Hatterrall Ridge (sometimes spelled Hatterall) is a ridge in the Black Mountains forming the border between Powys and Monmouthshire in Wales and Herefordshire in England. The ridge is about 10 miles (16 km) long, and is followed by the Offa's Dyke Path. On the west side of the ridge is the Vale of Ewyas, and on the east side is the Olchon Valley and Black Hill. The western side of the ridge falls within the Brecon Beacons National Park. Much of the northern part of the ridge is a broad whaleback, but it narrows down considerably further south, and especially near to Llanthony Priory in the Vale of Ewyas to the west of the mountain. There is a large and prominent landslip on the eastern side of the mountain here, known as Black Darren, where a large slice of the rocks has fallen away from the main mass of the hill. The ridge to the southwest ends abruptly at the sheer cliff known as the Darren below which is a considerable landslide area extending south to the hamlet of Cwmyoy with its misshapen church.

The Gospel Pass (Welsh: Bwlch yr Efengyl) is the highest road pass in Wales. It is at the head of the Vale of Ewyas in the Black Mountains of southeast Wales. Starting from Hay-on-Wye the narrow mountain road climbs steeply to a height of 549 metres (1,801 ft) above sea level, squeezing between the mountains of Twmpa to the west and Hay Bluff to the east, before dropping down into the valley to the south on its way to Llanthony Priory, Llanfihangel Crucorney and Abergavenny. At one time a small lead-mining operation was established at the pass. The Gospel Pass is one of the most celebrated locations within the Brecon Beacons National Park, being a popular destination for sightseers and is popular too with walkers and cyclists. Indeed, the Gospel Pass road forms a part of route 42 of the National Cycle Network. It also featured in the opening scenes of the film "An American Werewolf In London". It is a single track road over most of its length, but there are numerous passing places. Owing to its height and exposure, it is occasionally blocked by snow during the winter. It is well used by walkers since it gives access to the major peaks of the Black Mountains, especially at the northern end of the road, where there are several car parks.

Capel-y-ffin (Welsh for 'chapel of the boundary') is a hamlet near the English-Welsh border, a couple of miles north of Llanthony in Powys, Wales. It lies within the Black Mountains and within the Brecon Beacons National Park. The nearest town is Hay-on-Wye, some 8 miles (13 km) to the northwest.

Llanthony Abbey is a former Anglican monastic institution founded in 1869 by Joseph Leycester Lyne (Father Ignatius), in the Welsh village of Capel-y-ffin, a few miles from the medieval Llanthony Priory. It survived until 1908, after which it was the home of artist Eric Gill. It is now holiday accommodation. It was also known as Llanthony Tertia - following on from the nearby original medieval Llanthony Priory, and its Gloucestershire offshoot Llanthony Secunda - or New Llanthony Abbey. The surviving buildings are now referred to as Capel-y-ffin Monastery.

Craswall Priory was a Grandmontine priory in Herefordshire, England at grid reference SO27253770 dating from 1220 to 1225. The poor condition of the ruins mean that they are on Historic England's Heritage at Risk Register.

Twmpa or Lord Hereford's Knob is a mountain in south-east Wales, forming a part of the great northwest scarp of the Black Mountains. It lies 1.86 miles (3 km) west of the border with England, and around 4.34 miles (7 km) south of Hay-on-Wye. To the northeast lies the Gospel Pass through which runs a minor road between Hay and the Llanthony Valley. A ridge known as Darren Lwyd tapers away for about 3 kilometres (1.9 mi) to the southeast of the summit.

Craswall (historically also spelt Craswell, Crasswall and Crosswold) is a village and civil parish in Herefordshire, England. It lies in the far west of the county, in the foothills of the Black Mountains, close to the border with Wales. Before 1536 Craswall was in the marcher lordship of Ewyas. Until 1866 it was a chapelry in the large parish of Clodock (until 1852 in the diocese of St David's). It then became a separate civil parish.The village is near the source of the River Monnow. Above the village is the Black Hill, the setting for Bruce Chatwin's novel On the Black Hill. In the 2001 census the population of the civil parish was 147, increasing to 153 at the 2011 Census.

The Grwyne Fawr Reservoir is located in the valley of the river Grwyne Fawr in the Brecon Beacons National Park, Wales. Completed in 1928, it has the capacity to hold 400,000,000 imperial gallons (1,800 megalitres).

Hen-allt Common is a Site of Special Scientific Interest in Brecknock, Powys, Wales. Its special features include unimproved grassland, Flat-sedge Blysmus compressus and Meadow saffron Colchicum autumnale.