Penmoelallt facts for kids

Penmoelallt or Onllwyn is a cool hill located in the northern part of Rhondda Cynon Taff, a county in south Wales. It's a special place because it's part of the amazing Brecon Beacons National Park and the Fforest Fawr Geopark.

To the east of Penmoelallt, you'll find the deep valley of Cwm Taf. North of the hill, there's a smaller valley where the Nant Cadlan stream begins. To the west, there's another hill called Mynydd-y-glog. The southern parts of Penmoelallt lead down to the River Taff and the Afon Cynon. The top of the hill is a bit flat but has several small bumps that are higher than 420 meters (about 1,378 feet). Because the hill is covered in trees, it's tricky to find the exact highest spot. Old maps show a point that is 1,376 feet above sea level.

What Penmoelallt is Made Of: Geology

Penmoelallt is like a giant layer cake made of different types of rocks. These rocks were formed a very long time ago during the Carboniferous period. Over time, they tilted towards the south, forming part of the South Wales Coalfield.

The lowest and oldest rocks, seen on the northern and eastern sides, are Carboniferous Limestone. Above these, you'll find rough sandstones called Twrch sandstone. The southern parts of the hill are made of the lowest layers of Coal Measures.

There are also a couple of cracks in the rock, called faults, that run across the hill. The limestone areas have cool features like sinkholes, which are hollows formed when rock dissolves. You might also see some areas of exposed sandstone, but most are hidden by trees.

Exploring Penmoelallt: Access

Almost all of Penmoelallt is covered by a forest of cone-bearing trees. This forest is looked after by Natural Resources Wales. They have made the entire area open for people to walk and explore.

Many tracks run through the forest, but you can't drive on them with a car. There are also a few official public paths that cross the forest. Some of these paths can be a bit hard to find. A path for horses and walkers between Ffrwd Uchaf and Pen-twyn-isaf is also a forest track, making it easy to get to from Cwm Taf. The Taff Trail also follows a footpath in this area.

Special Trees: Ley's Whitebeam

Penmoelallt is home to a very rare tree called Ley's whitebeam (Sorbus leyana). This tree species is endemic to Wales, meaning it only grows naturally in Wales. Penmoelallt is one of only two places in the entire world where you can find this special tree growing wild!