It is a from a hill called Y Gyrn above the Storey Arms. The mountain is Fan Fawr. Here we find a watershed. To the south water runs down into the Taff Valley. To the North it runs into the Usk Valley. Do you recognise this view?

Today the Storey Arms is an outdoor activities centre near the A470, the main road from Cardiff to Brecon. Originally it was an Inn at the highest point on the rough road which linked Merthyr and Brecon. It was used as a resting place for travellers and horses alike. What do you know about the Storey Arms?

The River Taff starts its 30 mile journey to the sea high in the Brecon Beacons National Park. Its source can be found close to its highest peaks Pen-y-Fan and Corn du. It starts as 2 rivers the Taf Fawr and the Taf Fechan. Can you name these mountains?

Sketch map showing the Taf Fawr and Taf Fechan Can you trace the routes of the Taf Fawr and Taf Fechan on this map? What else can you see?

Pen-y-Fan is the highest peak in Southern Britain. It is 2907ft (886m) high. The flat tops on the mountains are caused by a layer of hard rock. Softer rocks above it have been worn away leaving the hard flat top. What do you know about Pen-y-Fan?

If we look south from Y Gyrn we see that the Taf Fawr has been dammed to create reservoirs. Here we can clearly see the Beacons reservoir and Cantref in the distance. A third reservoir lies further south this is called Llwyn Onn.. The A470 runs alongside these reservoirs. We can also see an area of forestry with some evergreen Sitka spruce trees. What can you see here?

Can you find these reservoirs on this OS map of the area? What other features can you find?

High in the mountains we find a natural lake called Llyn Cwm Llwch. Is this a natural lake or a man made reservoir?

Can you find this lake on this OS map of the area? What other features can you find?

Up in the mountains the ground is very wet and spongy. The water slowly drains from this marshy ground into streams. How does the river start?

Quite often this ground is peat. Here we can see this peat as it is being eroded.

Many of these streams run down the mountain sides. When they run over layers of hard rock we see waterfalls.

The streams run in to the young river which is fast flowing and has lots of energy.

The young river has cut a steep sided V-shaped valley in to the mountain.

Where it runs over layers of hard rock it forms waterfalls and plunge pools.