DSC02106 (1024x576) YouTube-Icon



Web Logo Picture1a DSC06596 (800x450) DSC09390 (1280x710)

The Tarennig and Bidno (pronounced Bidna) - (see Diary) rise in the Plynlimon massif or in the same general area. The Tarennig in fact emerges beneath the summit of Plynlimon itself whereas the Bidno rises 4KM East amid the bogs of the Esgair Y Maesnant on Waun Goch.


This is a water world up here for the rainfall is almost double that of Hay-On-Wye 700 meters lower down the valley. 2,400 mm of rain falls each year as opposed to 1,400 at Hay making these mountains and hills a veritable water tank. They're why the Wye exists.


Both are but small rivers measuring in length 8.5 KM (Tarennig) and 9km (Bidno). There are large plantations running alongside each river (Hafren Forest on the Bidno) altering their PH levels (see Conservation Page), which is the result of a plantations acidic nature. River PH levels affect invertebrates in the bed of the river, which in turn impacts upon spawning fish such as Salmon. Agencies like the Wye Usk Foundation are changing this by way of liming such rivers at source.


They are beautiful to walk but you walk you will come across old lead mine works on the Tarinneg, which were started in the 1800's whilst on the Bidno 4KM East you will come across a working estate complete with thousands of Pheasants alongside the right of way to the Bidno. Yes, we have the vistas and the wild sense you get up here but we also have industry.


Not to obscure the small details of the bog land fine examples of Sphagnum Moss exist amid the elephant grass and acid grassland. The mounds are striking with diamond like leaves or gametophores compacted together. The leaves glowing green grow constantly whilst the material below dies eventually compressed by the material above. Here, after 1,000 years you’ll see a meter of peat rich in carbon. Yes, these peat bogs up here are some of the finest carbon storage units in the world. They are invaluable and worth a look.

The Rivers of bog

The Plynlimon range, which is pronounced Pimlimon and means five peaks in Welsh is home, not just to the Tarennig and Bidno (Bidna) but also numerous other rivers. Situated in Northern Ceredigion the highest point is Plynlimon at 752 Meters or 2,467 Feet. The other four peaks are Pen Pumlumon Arwystli, Y Garn, Pen Pumlumon Llygad-bychan and Pumlumon Fach.  


Other rivers besides the Tarennig and Bidno have their source in the area and more specifically on the slopes of the Plynlimon range. These are the Wye, Severn and Rheidol.


The Severn flows into the Bristol channel via towns such as Shrewsbury and Gloucester. Whereas the Rheidol flows into Aberystwyth the Welsh coastal town some 15 KM East as the crow flies from its headwaters amid the Nant Y Moch Reservoir. It is a massive range.

Two rivers one mountain range

i'm inspired by the Wye

Rivers Tarennig & Bidno

Video: P1  

Video P2

We start the Tarennig hike at its confluence with the Wye nearby Pont Rhydgaled or the entrance to the Sweet Lamb Estate.


It is a river once visited some 5 years before, which stimulates many emotions.


The confluence is gentle but it is surrounded by rugged mountains in the heart of the Cambrian Mountains. It turns out to be a wet one.

The morning of day 2 starts above the Wye source and an old camp going back to 2014. (see Diary).


I was warned first thing not to camp on the private property. I apologised saying I was late in. I will ask permission if there is a next time. I respect the land.


At source it is super wet as is common on the Cambrian Mountains but the walk proves to be exhilarating.

The Tarennig flows through Eisteddfa Gurig (Eiesteddfa meaning seat), which is reputedly where the 7th Century St Curig a Celtic Roman Catholic Bishop rested on a mountain as he moved inland from Aberystwyth where he beached. The village of Llangurig further down the valley is named after him.

The Bidno flows passed the Southern tip of the Hafren Forest named after the Afon Hafren or River

Severn. It is a huge commercial plantation of Pine and Spruce, which was planted in 1937. It covers an area of 40 Sq KM.

Mountain or Region - Cambrian Mountains


Authority/District - Caredigion


Length of Rivers - Tarennig 8.5 KM, 5.2 Miles - Bidno 9KM, 5.6 Miles


Ascent to Source - Tarennig 645 Meters 2,116 ft - Bidno 470 Meters 1,541 ft


The walk up to source will take you over open access land. It is boggy and rough going and only suitable for experienced walkers. You can enjoy it from the Plynlimon right of way or from the summit of the mountain looking down.



Maps                        Sheet Finder



Ordnance Survey 1.25,000 Sheet Map 213 

Ordnance Survey 1.25,000 Sheet Map 214 

Anquet                  1.25,000 Digital Map 213

Anquet                  1.25,000 Digital Map 214

Ordnance-Survey-logo OMN_512_600x600 Uk_outline_map

How to get there by bus


From Hereford catch the Sargeants bus into Llandrindod Wells. From Llandrindod Wells catch the X47 bus to either Llangurig (for Bidno Valley) or Eisteddfa Gurig (Tarennig). To get close to the Bidno source and to enjoy a spectacular valley walk alongside it walk from Llangurig overland North West to Henfaes following public rights of way. Once there navigate to the road turning right at the road until you reach the rights of way for the Bidno valley, which are well marked on the map. From Cardiff or the South catch the T4 into Llandrindod Wells. To get to Rhayader and then Llangurig same as above. From the North/Shrewsbury catch the X75 to Llangurig or the T4 to Llandrindod Wells. To get to Bidno same as above.


All is applicable if walking the headwaters of the Tarennig. The only difference is that you are asking for Eiesteddfa Gurig. The scenery is fantastic along both river walks. In fact, whilst at the headwaters of the Tarennig you could even summit Plynlimon the highest peak in the Cambrian Mountains and source of the Wye.


There are fantastic  Bothy experiences in the area if you are intrepid enough.


How to get there by car


From the Midlands/Hereford take the A480 into Kington, then onto the A44 into Rhayader. Once there turn right out of town onto the A470 until you reach Llangurig. If heading for the River Bidno and Valley carry on through the village left onto the A44 for3 miles being careful to spot the small right turning off at Penlon. Take the turning and head into the valley for 2KM. Car parking will have to be creative.

From Cardiff or the South take the A470 to Brecon. From Brecon take the B4520 into Builth Wells. From Builth take the A470 into Rhayader. To get to LLangurig and the Bidno Valley same as above. From the North Wrexham take the A483 to Newtown, From Newtown take the A489 onto the A470 into Llangurig. Directions to Bidno and Valley same as above.  From Shrewsbury take the A458 onto the A483 Newtown, then onto the A489 for a short distance before the A470 to Llangurig. Directions to Bidno and Valley same as above.  


If heading for the River Tarennig and Valley the same applies only you are driving further from Llangurig on the A44 to get to Eisteddfa Gurig where there is car parking. It’s a good river and mountain walk.


There are fantastic Bothy experiences in the area if you are intrepid enough.