3.0
(1)
348
runners
17
runs
Jogging around Llyn Arenig-Fawr offers a challenging experience within Snowdonia National Park, characterized by rugged mountain terrain and a secluded reservoir. The area features the imposing Arenig Fawr mountain, with its steep cliffs and heather-covered slopes. Trails consist of a mix of tracks, stony ground, and potentially boggy sections, providing varied conditions for runners. This landscape offers both demanding uphill climbs and flatter sections closer to the llyn.
Last updated: July 8, 2026
8
runners
9.93km
01:30
530m
530m
Hard run. Very good fitness required. Mostly paved surfaces. Suitable for all skill levels.
9
runners
15.4km
02:23
700m
700m
Hard run. Very good fitness required. Mostly paved surfaces. Suitable for all skill levels.

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11
runners
15.0km
02:03
550m
550m
Hard run. Very good fitness required. Mostly paved surfaces. Suitable for all skill levels.
9
runners
17.9km
02:33
740m
740m
Hard run. Very good fitness required. Mostly paved surfaces. Suitable for all skill levels.
5
runners
11.9km
01:44
520m
520m
Hard run. Very good fitness required. Mostly paved surfaces. Suitable for all skill levels.
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The memorial is right next to the summit cairn, and is suitably low key for such a location and what it commemorates.
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As the Arenig Fawr is an isolated peak the views in all directions are very good - including to the nearby Rhinogs.
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The secondary top of Arenig Fawr, but with equally good views.
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A lovely little lake (Llyn) in the shadow of Arenig Fawr, a great place for reflections when the weather is bright and calm.
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Artificially enlarged, this beautiful lake provides perfect reflections of the mountain above. Wonderfully peaceful place you will often have entirely to yourself.
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A fine summit atop an isolated peak so there are wide views in all direction. Also a very fitting memorial.
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Arenig Fawr's smaller neighbour, but great views back to Arenig Fawr itself.
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This old cottage is in the process of being rebuilt, but the farmstead next to it is still in ruins.
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There are 18 running routes available around Llyn Arenig-Fawr. These include 9 moderate and 9 difficult trails, offering a range of challenges for runners.
The terrain around Llyn Arenig-Fawr is rugged and varied, characterized by heather-covered slopes, stony ground, and tracks. You can expect challenging uphill climbs, especially towards the summit of Arenig Fawr, and potentially boggy sections, particularly in wet weather. Some upland areas above 750m can be exposed.
The routes around Llyn Arenig-Fawr are generally considered challenging. There are no easy routes listed; all 18 routes are either moderate or difficult. The track leading to the reservoir offers a relatively clear beginning, but the overall environment is better suited for those seeking a more rigorous experience.
For experienced trail runners seeking a challenge, routes like the Arenig Fawr South Ridge Top – Moel Llyfnant loop from North Wales, an 11.3-mile difficult trail, offer significant elevation gain and varied mountain terrain. Another demanding option is the Arenig Fawr South Top – Llyn Arenig Fawr loop from North Wales, which is 9.3 miles and combines the mountain's challenging terrain with views of the secluded llyn.
While running around Llyn Arenig-Fawr, you'll encounter dramatic landscapes dominated by the imposing Arenig Fawr mountain and the secluded reservoir itself. From the summit of Arenig Fawr, you can enjoy spectacular 360-degree panoramic views of most mountain summits in Snowdonia on clear days. There's also a memorial at the summit to an American aircrew, adding a poignant historical element.
Yes, Llyn Arenig-Fawr is often described as less visited compared to other peaks in Snowdonia, offering a strong sense of solitude and peace. This quiet atmosphere can enhance the meditative aspect of a long run, making it ideal for those seeking a secluded outdoor experience.
Yes, there are several circular running routes. For example, the Arenig Fawr loop from Capel Celyn is a difficult 6.2-mile circular trail that ascends the rugged slopes of Arenig Fawr. Another option is the Running loop from North Wales, a difficult 7.4-mile route.
The best time of year for running around Llyn Arenig-Fawr generally depends on weather conditions. While the panoramic views are stunning on clear days, the area can be boggy, especially in wet weather. Upland areas are exposed, so checking local weather forecasts is crucial, particularly outside of warmer, drier months.
While specific parking locations are not detailed in the route descriptions, access to the Llyn Arenig-Fawr area typically involves reaching Capel Celyn or other starting points in North Wales. It is advisable to research designated parking areas or roadside parking options near your chosen trailhead before your visit, as facilities can be limited in remote mountain regions.
The running routes in Llyn Arenig-Fawr are highly rated by the komoot community, with an average score of 3.0 stars. Over 200 runners have used komoot to explore the varied and challenging terrain, often praising the rewarding views and the sense of accomplishment from tackling the rugged mountain environment.
While many trails in Snowdonia National Park are dog-friendly, it's important to be mindful of livestock, especially sheep, which are common in the area. Always keep dogs under close control, preferably on a lead, to protect wildlife and livestock. Some sections may also be challenging for dogs due to rocky or boggy terrain.
The routes directly around Llyn Arenig-Fawr are generally considered moderate to difficult, with rugged mountain terrain. For families seeking less strenuous options, the nearby Bala Lake – Llyn Tegid loop from Llangywer offers a moderate 8.6-mile route with minimal elevation gain, providing a more accessible experience.


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