Beautiful Llyn y Fan Fach Walking Routes

Llyn y Fan Fach is a glacial lake in the Brecon Beacons (Bannau Brycheiniog), situated beneath Picws Du mountain. This beautiful lake is steeped in Welsh Folklore and is listed as one of the 1000 must-see places in the world by the Lonely Planet.

Further to the east, beneath the peak of Fan Brycheiniog, there is another larger lake called Llyn y Fan Fawr. These lakes and peaks can be visited through a combination of mountain walks and are collectively known as the Carmarthen Fans.

This hiking guide describes 5 walking routes which take in views of these beautiful lakes. I provide trail descriptions, distances, times and pinned starting locations.

Picws Du mountain and Llyn y Fan Fach lake

The Black Mountain (singular) refers to the range of mountains in the Western Brecon Beacons National Park where Llyn y Fan Fach/Fawr are located. This is not to be confused with the Black Mountains on the Eastern side of the Park.

The highest peak in the Black Mountain (Y Mynydd Du) range is Fan Brycheiniog at 802m. This range of mountains displays breathtaking examples of glacially formed cwms (or valleys), lakes and escarpments.

For me, this remote western side of Bannau Brycheiniog (The Brecon Beacons) offers the best Beacons walking and attracts very view visitors, compared to the Central Beacons and the Black Mountains in the East.

For years locals have revelled in having this glorious spot on their doorstep, but in 2020 popularity boomed after appearing on the BBC’s Secret Britain and being voted the UK’s number 1 Hidden Gem by Hayes and Jarvis.

For information on other top hikes in the Brecon Beacons, click here!

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The 5 Best Llyn y Fan Fach/Fawr Walks

There are multiple walking routes that allow you to enjoy the Black Mountain range with views of Llyn y Fan Fach and Llyn y Fan Fawr. Below I outline five walks of differing lengths and difficulty that explore this beautifully secluded region.

Tips on Pronunciations and Meanings 

  • Llyn y Fan Fach – Small lake (near) the peak: Thlin er Van Var-ch where the ch is soft like loch
  • Llyn y Fan Fawr – Big lake (near) the peak: Thlin er Van Vaw-oor
  • Fan Brycheiniog – King Brychan’s Peak: Van Brih-chein-ee-og where the ch is soft like loch
  • Fan Hir – Long Peak: Van Hee-r
  • Picws Du – Black Mountain: Pic-oos Dee
  • Fan Foel – Bare Peak: Van Voil

Want to learn more about how to pronounce Welsh words? If so, take a look at this post!

Before you go:

  • The Llyn y Fan Fach car park near Llanddeusant is remote with no facilities, although there are port-a-loos further along the track at the workers base. The final section of road to access this car park is single track with only a few passing places.
  • The layby on Heol Lan is also very secluded with no nearby facilities so make sure you have everything you need before you arrive.
  • Click on the blue link in the route description for each walk to see the starting location in Google maps.

1. An Easy Llyn y Fan Fach Walk 

  • Distance: 8 km (5 miles)
  • Elevation Gain: 470m (1541ft)
  • Time: 3 hours
  • Difficulty: Moderate
  • Starting Point: Llyn y Fan Fach Car park, Llangadog, Llanddeusant SA19 9UN

From the car park follow the gravel road uphill as it immediately follows the Afon Sawdde river. This is a gradual climb past multiple small waterfalls and cascades that leads to a beautiful reveal of Llyn y Fan Fach.

Top Tip: If you want an easy Llyn y Fan Fach walk, simply retrace your steps from here and walk back to the car park. This would make a short 4km loop.

After enjoying some time soaking in this great amphitheatre, continue around the lake to the west and ascend the ridge. The views from the top of this dramatic escarpment are well worth the climb.

Llyn y Fan Fach aerial photo
Llyn y Fan Fach from atop the ridge

Follow the path along the ridge to the north-east, keeping views of the lake down to your left. Climb to Picws Du (Bannau Sir Gaer) which is the second highest peak in this range, before dropping down into the saddle.

At this point bear left down a steep gulley trail which zig zags down the escarpment. Once at the bottom, take the trail to the left to head back in the direction of the lake. Follow the riverside path back down the valley to the car park starting point.

This loop is a great Llyn y Fan Fach short walk which provides incredible views in all directions, however the path down from Picws Du is very steep with some loose scree and exposed edges. This might not be not suitable for small children.

Pro Tip: To extend this walk, rather than turning left down into the gulley, continue up the other side of the saddle onto Fan Foel peak. At the summit cairn, turn left and descend down the shoulder. Continue along the path in a northeasterly direction, as it gradually descends back to the car park. This is my favourite Black Mountain walk since it provides amazing views of both lakes and isn’t as long as some of the other walks. This is the route shown in the video above.

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2.  Llyn y Fan Fach and Llyn y Fan Fawr Circular Walk from Llangadog

  • Distance: 15 km (9.3 miles)
  • Elevation Gain: 739m (2425ft)
  • Time: 6 hours
  • Difficulty: Strenuous
  • Starting Point: Llyn y Fan Fach Car park, Llangadog, Llanddeusant SA19 9UN

From the car park follow the gravel road along the Afon Sawdda to reach the first lake of the hike – Llyn y Fan Fach. At this point leave the gravel trail and take the path to the right of the lake to ascend the ridge.

At the top, continue along the ridge path with magnificent views of the lake down to the left. After reaching the high point on this ridge of Picws Du (Bannau Sir Gaer), descend the saddle before climbing steeply back up to the next ridge.

The most northerly point of this peninsula is Fan Foel peak at 781m, which is marked with a cairn. At this point the trail heads in a southerly direction and you can now see the second lake of this hike, Llyn y Fan Fawr. Translating to lake of the big peak, this is one of the largest lakes in Wales.

Views of Llyn y Fan Fach and Picws Du
Looking back towards Picws Du and Llyn y Fan Fach from Fan Foel. Discover more photographs of Llyn y Fan Fach here.

Continuing along the path you will next reach the highest point on this hike and indeed in this region – Fan Brycheiniog. At this point on clear days, you will be rewarded with fabulous views of the highest peak in the Brecon Beacons, Pen y Fan. Discover my favourite routes to the summit of Pen y Fan in this guide.

Leaving Fan Brycheiniog, the descent begins. 600m after leaving the peak a path breaks off to the left to steeply descend down to the Llyn y Fan Fawr. This set of stone steps is known as the ladder.

Louise France standing above Llyn y Fan Fawr
Taking a moment to enjoy the views on the steep path to Llyn y Fan Fawr

Once at the lake, take the path that veers off to the left and circles the eastern (far) side of the lake. Follow this path to the northern end of the lake before taking the path on the left that leads towards to base of the escarpments.

Once on this path simply skirt the ridges that you walked on top of earlier, until you return to Llyn y Fan Fach. From the lake, retrace your steps along the path that returns to the car park.

Now Available

Bannau Brycheiniog Hiking Routes

Hiking routes include the ever popular Pen y Fan, Llyn y Fan Fach, Sugar Loaf and the Four Falls.

Enjoy 35 beautiful hikes in Bannau Brycheiniog (the Brecon Beacons) with the help of my pre-planned hiking routes. I have 35 beautiful hiking trails marked out on the free, offline app Simply download my pins into the app and choose which one of these epic hikes you’d like to enjoy!

3. Llyn y Fan Fawr and Llyn y Fan Fach Circular Walk from the A4067

  • Distance: 20km (12.4 miles)
  • Elevation Gain: 1023m (3359ft)
  • Time: 7 – 9 hours
  • Difficulty: Strenuous
  • Starting Point: Tafarn Y Garreg Pub Car Park

Also known as the Carmarthen fans, this hike starts from a car park next to the Tafarn Y Garreg Pub, on the A4067. This is a full day which, due mostly to the distance, is considered a strenuous walk. This is also the starting point for a walk to explore the Carreg Goch Wellington Bomber crash site.

From the car park, cross the road and join the footpath which immediately begins a steep ascent. This fairly quickly becomes a ridge which leads to the first summit of the day, Fan Hir. From here you will get the first views of Llyn y Fan Fawr down below.

Fabulous ridge walking towards Llyn y Fan Fawr
Nick walking along the ridge of Fan Hir

There is a short descent to the saddle before climbing once again to the top of Fan Brycheiniog. Continue along the ridge a little further to bag the next summit of Fan Foel, after which the trail turns in a westerly direction.

Again there is a small descent to the next saddle before climbing to the summit of Bannau Sir Gaer (Picws Du). Enjoying views now of Llyn y Fan Fach, continue along the ridge to take in the final peak of Waun Lefrith, before beginning the main descent.

Branch off the ridge to the right in an easterly direction to walk down to the lake. This is roughly the halfway point and a good place to take a well earned break.

Nick walking beneath the ridges towards the base of Fan Foel

From the lake, the path now skirts the base of the escarpment as it continues in an easterly direction. After contouring beneath Fan Foel, the trail begins to head south towards Llyn y Fan Fawr.

Walk along the easterly edge of the lake to fully admire its beauty and then start the gradual descent back towards the car park. There are several pretty little waterfalls to admire as a final reward along the last few kilometers. This last section is rocky and can be quite boggy.

4. Fan Hir, Fan Brycheiniog and Llyn y Fan Fawr Loop (Drovers Trail)

  • Distance: 15.6 km (9.7 miles)
  • Elevation Gain: 766m (2513ft)
  • Time: 6 – 7 hours
  • Difficulty: Strenuous 
  • Starting Point: Tafarn Y Garreg Pub Car Park

Follow directions for the previous hike to the summit of Fan Foel. Enjoy views looking down onto Llyn y Fan Fach to the west and Pen y Fan to the  east. From this peak, instead of turning left towards Picws Du, continue along the path in a northerly direction as it descends the shoulder.

Once at the base of Fan Foel, turn right and follow the path back towards Llyn y Fan Fawr. Again walk around the easterly edge of the lake and follow the trail along the gradual descent back to the car park at Tafarn y Garreg.

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5. Short Llyn y Fan Fawr Walk

  • Distance: 5km (3 miles)
  • Elevation Gain: 160m (525ft)
  • Time: 2 – 3 hours
  • Difficulty: Easy-moderate
  • Starting Point: Layby on Heol Lan

This walk begins from a layby on Heol Lan road. It’s located 5.5km after turning onto Heol Lan from the A4067. This layby has enough space for just a few cars. This is also the starting location for a hike to see the Vampire jet VZ106 crash site.

From the layby follow the path to the left. The path to the right heads uphill to a viewpoint which isn’t necessary for this walk. The path skirts around the hill, down into a valley before beginning the gradual climb up towards Llyn y Fan Fawr. 

The path roughly follows a stream most of the way, leading you to the south end of the lake. Several small gullies and streams will be crossed along the way. A loop of the lake is around 2km so this can be added to your walk if you want to enjoy the lake from all sides.

To complete the walk simply retrace your steps back to the lay-by on Heol Lan.

Llyn y Fan Fawr in the snow
Exploring Llyn y Fan Fawr from the south during a snowy sunet

If you’d like all of these hiking routes planned out on one map, take a look at my Llyn y Fan Fach/Fawr hiking route pins here! The routes are pinned on the free app

All the routes to Llyn y Fan Fach and Fawr on one map
All the routes around Llyn y Fan Fach/Fawr

Lady of the Lake – The Lyn y Fan Fach Legend

As with many places in South Wales, Llyn y Fan Fach is steeped in Welsh folklore. According to this legend, a young farmer was grazing his animals when a beautiful lady walked out of the water. He fell instantly in love with her. She agreed to marry him but only on the condition that he must not strike her 3 times.

They were happily married for many years and had 3 sons together. However, as you might imagine this happy story didn’t last. Versions of the myth differ as to the nature of these strikes, but sure enough the farmer did indeed strike his wife 3 times. On the third occasion, true to her word, she left and vanished back into the cold waters of the lake, leaving the farmer eternally heartbroken.

There are more Welsh folklore tales linked to walks throughout the Brecon Beacons, in particular the walks in Waterfall Country.

Sunrise over Llyn y fan Fawr
Llyn y Fan Fawr at sunrise

Transport to Llyn y Fan Fach & Llyn y Fan Fawr

The starting location for these hikes is very remote so if you’re relying on public transport your options will be limited. The T6 bus from Swansea to Brecon stops at Tafarn y Garreg Inn, which is the starting point for routes 3 & 4. See the bus timetable here. Tafarn y Garreg also offers camping if required.

For the other routes you’ll need use of a car. For the best deals in car rentals in the UK, I suggest Rental Cars.

What to pack when hiking the Carmarthen Fans

These are just some of the essentials, but for a complete list of things to take on a day hike, take a look at this guide!

Hire A Local Guide

Prefer not to walk alone? If you’re looking for a Mountain Leader to guide you on a mountain adventure, please contact me here to discuss rates and availability.

Where to Stay in the Brecon Beacons

The Brecon Beacons has several cute market towns and villages to use as a base for exploring the national park. There aren’t many large chain hotels but instead, you will find a selection of bed and breakfasts, pubs/Inns, glamping and camping opportunities.

As a central location, you can’t go far wrong with the town of Brecon. The beautiful Camden Lodge B&B offers exceptional service, with large, clean rooms that have delightful views over the hills. To experience the charm of a cosy, local pub try the Usk and Railway Inn at Sennybridge. This is a fabulous location for mountain bikers looking to get out in the hills.

If you’d prefer to be based near the Black Mountains in the east, opt for the Ty Croeso Boutique B&B which is an exquisitely renovated Victorian building located near the small town of Crickhowell. In the west, Cwtch Bach is a gorgeous stone bricked holiday home perfect for exploring The Black Mountain region.

For a luxury glamping experience try the Cuddfan, whose bell tent located along the banks of the river Grwyne offers a real escape back into nature. For more luxury glamping ideas take a look at this guide to glamping in the Brecon Beacons.

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Walking routes of Llyn y Fan Fach and Llyn y Fan Fawr

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Louise is a Mountain Leader and Snowboard Instructor from South Wales. As a former Adventure Tour Leader she has spent the last 15 years travelling Asia, Africa and the Americas. Louise is a published photographer and is currently based in the UK.

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