Cadair Fawr

Cwm Cadlan is a Site of Special Scientific Interest in Glamorgan, south Wales. It is made up of a series of wet grassland fields in a small valley to the north west of Merthyr Tydfil. It is also designated as a Special Area of Conservation (SAC) and a National Nature Reserve (NNR).

Mynydd-y-glog is a hill just east of the village of Penderyn in the northern corner of the county borough of Rhondda Cynon Taff in south Wales. It lies within the Brecon Beacons National Park and Fforest Fawr Geopark. Its summit plateau rises to a height of 389m / 1277 ft at OS grid ref SN 982088, a spot marked by a trig point. To its north lies the partly dry valley of Pant Sychbant which forms the eastern extension of Cwm Cadlan. Its southern slopes are drained by various streams which feed into the Afon Cynon.

Penmoelallt or Onllwyn is a hill in the northern part of the county borough of Rhondda Cynon Taff in south Wales. It lies within the Brecon Beacons National Park and Fforest Fawr Geopark. To its east lies the deep valley of Cwm Taf and to its north a rather shallower valley in which the Nant Cadlan originates. To the west is the hill known as Mynydd-y-glog and to the south are slopes draining into the River Taff and the Afon Cynon. The hill culminates in a broken plateau with several knolls rising above the 420m contour. Its afforested nature makes it difficult to determine the precise location of its highest point but this probably lies somewhere around OS grid ref SO 003096. Older maps indicate a spot height of 1376 ft above sea level at SO 000090.

Llwyn-on Reservoir (or Llwyn Onn Reservoir) is the largest and southernmost of the three reservoirs in the Taf Fawr valley in South Wales. Cardiff Corporation Waterworks obtained an Act of Parliament in 1884 to authorise construction of the reservoirs, to increase the water supply for Cardiff, but construction of Llwyn-on Reservoir did not start until 1911 and was completed in the 1920s. The reservoir, which has been owned and managed by Welsh Water and its predecessor organisation, the Welsh Water Authority, since 1973, is located within the Brecon Beacons National Park with its eastern half in the Merthyr Tydfil unitary authority area and the western half in Rhondda Cynon Taf. The village of Llwyn-On is nearby and the A470 trunk road runs along its eastern shoreline.

The Penderyn television relay station is sited on high ground to the east of the village of Penderyn in the Brecon Beacons. It was originally built in 1984 as a fill-in relay for UHF analogue television covering the communities of Penderyn and Hirwaun. It consists of a 12-metre (39 ft) self-supporting lattice steel mast standing on a hillside which is itself about 310 metres (1,020 ft) above sea level. The transmissions are beamed west and south to cover all these targets. The Penderyn transmission station is owned and operated by Arqiva. Penderyn transmitter re-radiates the signal received off-air from Carmel about 30 miles (50 km) to the west. When it came, the digital switchover process for Penderyn duplicated the timing at Carmel with the first stage taking place on 26 August 2009 and with the second stage being completed on 23 September 2009. After the switchover process, analogue channels had ceased broadcasting permanently and the Freeview digital TV services were radiated at an ERP of 2.6 W each.

Woodland Park and Pontpren is a Site of Special Scientific Interest in Rhondda Cynon Taf, south Wales. The site consists of three separate blocks of land, approximately 1 km (0.62 mi) south of the village of Penderyn. The Countryside Council for Wales states that the site has been categorised as a Site of Special Interest "...for the Marsh Fritillary butterfly. Additional special interest is provided by its mixture of habitat types, including marshy grassland, dry acid and neutral grassland, heathland and woodland, which add to the ecological and biodiversity interest of the site and which also provide food and shelter necessary for the survival of the Marsh Fritillary."

Bryncarnau Grasslands, Llwydcoed is a Site of Special Scientific Interest in Llwydcoed near Aberdare, south Wales.

Merthyr Road railway station served the village of Hirwaun, in the historical county of Glamorganshire, Wales, from 1851 to 1853 on the Vale of Neath Railway.

Hirwaun was a railway station serving the village of Hirwaun in Rhondda Cynon Taf, Wales.

Daren Fach is a Site of Special Scientific Interest in Merthyr Tydfil, south Wales.

Soar, Hirwaun was a Wesleyan Methodist chapel in Station Road, Hirwaun, Aberdare, Wales.

Ysgol Gyfun Rhydywaun is a Welsh-medium comprehensive school in the Cynon Valley in the village of Penywaun, Rhondda Cynon Taf, Wales, to the northwest of the town of Aberdare. The school was established on 1 September 1995 to deal with the increasing numbers of students attending five local Welsh-medium primary schools, who previously had to travel to secondary school in Pontypridd. It provides a Welsh-medium education for pupils from the Cynon Valley and from neighbouring Merthyr Tydfil County Borough, where there is no Welsh-medium secondary school.