Arenig Fawr

Arenig Fawr is the most naturally beautiful mountain in all Snowdonia National Park, with 360 degree summit views, a stunning mountain reservoir and the cutest bothy in the world.

The summit of Arenig has one of the most far reaching views in the entire national park. In the immediate region it’s possible to clearly see the Rhinog mountains, Snowdon, the Glyderau, Tryfan, the Berwyn mountains and the Carneddau.

On particularly clear days it’s possible to see the mountains of the Wicklows and Mournes in Ireland, as well as the higher peaks of both the Lake District and Peak District.

Llyn Arenig is a mountain reservoir located a way down from the summit, which feeds the Bala area with drinking water. Adjacent to the lake is a tiny stone bothy, with just enough room for 4 to sit on two tiny wooden benches, with a great little fireplace. We’ve enjoyed so many hours here, both as a break during day out wandering and nights out with the fireplace roaring.

Arenig Fawr holds a huge number of amazing memories for us, having visited in every weather condition possible and built a huge collection of unforgettable experiences.

Our Favourite Arenig Trail Route


Distance 5.9 miles

Time 2 to 3 hours (walking) / 1 hr 15m (running)

Total Ascent 1,868ft

OS Maps click to open this route on the OS Maps website

Summits Arenig Fawr.

Views 360 degrees of pure mountains and massive horizon landscape, off the chart on a clear day.

Arenig Fawr 3D Map

Arenig Fawr is in our opinion the most all round beautiful place in the entirety of Snowdonia National Park. The summit views are a full 360 degrees of uninterrupted wonder, the bothy is possibly the cosiest trail retreat ever, the lake is staggering….and on and on….

NOTE: the descent on this trail route is completely off trail for a long section. This means no path, no clear route and many obstacles. It’s also very boggy, meaning wet feet throughout the year. It took doing this mountain many many times to feel comfortable going at any speed over this route.

Reaching the summit of Arenig Fawr and returning the way we came is the route we use in either the toughest conditions or on lazy wandering days.

1. For years we’ve parked at an unused open space of land just opposite the quarry, but it was blocked off in around August 2019. There are a number of small laybys and spaces to park safely around this area. The route starts with a bit of normal tarmac road to warm the legs up, eventually getting a lovely view of Llyn Celyn just as the trail path heads off to the right through a small silver metal stile and up the hill.

2. The path snakes around and finally levels out as the view of Llyn Arenig lake begins to appear. A short descent ends by the lake with the tiny open stone bothy cottage, a fantastic place to rest up.

3. The real ascent begins from here, crossing the reservoir stream and following the ridge line to the left of the lake. The path clearly continues onwards and upwards, crossing a couple of small fences and a short levelled out section with boggy ground. After this the best way to summit is follow a footpath across to the left, staying at a constant elevation, and then crossing the boulders and scree diagonally to the top. The summit itself is fantastic, with unimaginably good views in literally every direction. The stone circle is two sided and provides decent wind break cover in most conditions.

4. Descending is a choice of challenge at this point: on lazy days and harsh conditions we often retrace our footsteps and go back the same way we came. However, this trail route is for an off trail descent that provides a ton of physical and mental challenge to cross. There’s no path for the last quarter of this Arenig Fawr trail route, it’s across completely overgrown ground with many boulders, foot holes and tough obstacles. But we find it insanely good fun. The toughest section is over when we get to the unmarked reservoir, then we cross to the edge of the old quarry and follow the narrow path back to the start.

Arenig Fawr FAQ

Essential information about this fantastic Snowdonia mountain.

Arenig Fawr is located near Llyn Celyn Reservoir, between the towns of Bala and Trawfynydd. The main areas to park for visiting the mountain are on an unmarked road off the A4212 main road.

At a comfortable walking pace the summit is reachable within a couple of hours.

Visit our Arenig Fawr Trail Route page for full details.

The summit trig point has a memorial to eight American aircrew who died when their Flying Fortress bomber B-17F #42-3124 crashed on 4th August 1943.

Some of the crash wreckage is still scattered across the hillside and visitors often move discovered parts next to the memorial plaque.

Two artists used Arenig mountain in their work in the early 1900s, focused on in a BBC documentary entitled “The Mountain That Had To Be Painted” in 2011.

A small village in Worcestershire claims to have a boulder originating from Arenig, believed to have been brought by the last ice age.

Christmas Morning 2019 @ Arenig Fawr

We were out the house at 5.45am on Christmas Morning and on the road to Arenig to receive nature’s gifts. Sat in a great spot amongst the boulders approximately halfway up the mountain, we were treated to this magical sunrise. After a jog down we stopped at the bothy for coffee and breakfast, the sun pouring in through the single window with a sublime view of Aran Fawddwy post sunrise.

The first 3 photos are our favourites from the morning; the glorious red to pink fade over Aran Fawddwy just before the sun appeared, the beams as it passed over the distant mountains behind the clouds and thirdly Sian & the dogs sat in the bothy in the sun’s glow.

There’s a short timelapse video from the GoPro of the whole sunrise, and lastly a “before/after” – on the way up in darkness and wandering down to a stunning pastel blue sky and open landscape.

Autumn Day at Arenig

Short video highlights from a trip to Arenig Fawr on a crisp autumn afternoon in 2019, with multiple timelapses around Llyn Arenig Fawr lake and a Llyn Celyn sunset timelapse at the end of the video.

Arenig Photo Gallery

Some of our favourite memories from many visits to Arenig Fawr in all weather conditions, from summer sun to winter snow.

Night Sky Photos

These images were taken on our GoPro Hero 7 action cameras. The stars are breathtaking on clear nights at Arenig, the lack of any nearby street lighting making it impossible to count the little white dots. Wild camping here can be an truly humbling experience.

Arenig Fawr Bothy

Possibly the cutest bothy in the world, Arenig’s tiny stone shelter houses two small benches, a shelf, a fireplace and not much else.

That being said, we’ve spent so many hours here and had a great many laughs. The fireplace gets the small room cooking hot even on the coldest of winter days and it’s a great place to cook up some food while the sky goes pink through the sole window.

As with all bothies, there’s a code to follow from the Mountain Bothy Association. In short, take logs/kindling/firelighters/candles and gift what you don’t use for others. Don’t leave rubbish and make an effort to tidy up if you happen to stumble across a messy bothy.