Llyn y Fan Fawr and Llyn y Fan Fach surely offer one of the best wild walks in Bannau Brycheiniog/the Brecon Beacons, says Steve Eddy.
Remote glacial lakes edged by swooping escarpments, long lonely pathways with awe-inspiring views await you. This route crosses the rocky river Tawe. It ascends gradually to the lovely Llyn y Fan Fawr (Lake of the Big Peak) where you could almost expect a hand to emerge holding Excalibur aloft. Then, drop down to Llyn y Fan Fach (Lake of the Small Peak), which has its own legend of an otherworldly woman emerging from the waters to marry a mortal, eventually abandoning him and returning to the lake when he gives her ‘three causeless blows’.
A steep ascent up to Waun Lefrith is rewarded by expanding views of the mirror-like lake below and the rolling peaks of Bannau Sir Gaer and Fan Brycheiniog. On a clear day, you’ll see Pen y Fan to the east, and the Preseli Hills to the west. The easy last leg, the gradual ridge descent of Fan Hir, is particularly lovely in evening sunlight. Nonetheless, this is a long walk, so it pays to start early!
Llyn Y Fan Fawr and Llyn y Fan Fach: route description
START/FINISH: lay-by next to Tafarn-y-Garreg; SN848170 (free parking) | MAPS: OS Explorer OL12 Landranger 160 | DISTANCE: 21km / 13 miles | ASCENT: 986m | DURATION: 7 hours
1. SN848170: Cross the A4067 to a signed public footpath. Pass through gates to a footbridge over the river Tawe, and follow a level path alongside the river to a metal gate. This leads onto a short track heading west towards the farmhouse of Ty Henry. Pass through a gate and over a stile, and skirt round a sheep pen, onto moorland signed as open access National Park land. Follow the Beacons Way northwards by the fence, crossing the stream of Nant Tawe Fechan near a small waterfall and a rowan tree. Stay on the clear path, which gently climbs mounds of glacial moraine, with the steep slopes of Fan Hir to your left, then falls to the shores of Llyn y Fan Fawr.
2. SN832213: Continue northwards along the path flanking the eastern bank of the lake. Halfway along its northern shore, still following the Beacons Way, leave the lake and climb north-west to Gwal y Cadno. Then traverse the base of Fan Foel, curving left and south-west after Gwely Ifan y Rhiw. Follow this path to Pant y Bwlch, crossing a small stream. Keep on to a fork in the path.
3. SN810221: Follow the small path for about 500m to another fork, one turning right to cross a water channel to the lake, and the other heading towards the weirs at the north-eastern corner of Llyn y Fan Fach. Don’t take either of these. Instead, strike out south-east towards the south of the lake. Then follow the lakeshore path round to where a stream enters at its north-west corner. Here, follow the stream uphill for 150m to an area of scree. Then take a path heading west-north-west to join the main path climbing from the weirs and dam.
4. SN800220: Climb steeply up westwards, past hurdles erected to stop path erosion, to rejoin another section of the Beacons Way looking down on the lake. Follow the clear path southwards, then east along Bannau Sir Gaer. Follow the sometimes indistinct but easy path gently up to a cairn on the summit of Picws Du (749m), then down to a small stream at Nentydd Blaen-Twrch. From this point, branch off onto the Cambrian Way. If you lose the path, head due east to reach the trig point at the summit of Fan Brycheiniog (802m), the highest point of the walk. Alternatively, go the long way: keep on the Beacons Way, hugging the edge of the escarpment to the cairn at Fan Foel (781m), then take the level path to the trig point and small circular shelter on the summit of Fan Brycheiniog. This will add 2km to the route.
5. SN825218: From the trig point on Fan Bricheiniog, follow the Beacons Way along the edge of the steep Fan Hir escarpment. (Take care in conditions of poor visibility, high winds or snow.) The path dips down briefly to Bwlch Giedd, then passes a sheep shelter. Keep on the path, the escarpment becoming less steep, then turn left, eastwards, through bracken, to reach the stile by the sheep pen near Ty Henry farmhouse. Then retrace your steps to the footbridge and the starting-point.
Public transport: Buses between Brecon and Ystradgynlais
Tourist information: Bannau Brycheiniog National Park visitor centre, 01874 623366
NEAREST YHA: YHA Brecon Beacons
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