In the north-west of Ireland, you will find wild mountains being left to nature, with narrow trails winding over ridges and wrapping around hillsides. You’ll find silence, and then the thousand tiny sounds of nature will fill your ears.

Overview

Distance: 10 - 12km
Format: Looped trail
Time: 2.5 - 5hrs, depending on how long you want to explore!
Parking: the primary parking for this loop is the Letterkeen Trail Head (Google Maps link). If you’re visiting and it’s busy, there is another car park about a 15 minute walk away: Sragrevagh Trailhead (Google Maps link). Letterkeen can suffer from overcrowding, so if you’re coming as a group (especially in the summer) carpooling is advisable.
Trail difficulty: Easy - Moderate
This is a waymarked route with purple arrows. You walk along riverbanks, stony valley floors, forest trails and woodland. Read how we rate trails here.
Trail quality: 5/5
This has long been one of my favourite trails. The terrain underfoot is great - with no road walking, and only a short while on forestry access tracks towards the end.
Views: 5/5
For a trail that only reaches a high point of 311m, the views of the surrounding mountains are fantastic.
Buggy/Wheelchair friendly: No
Dogs allowed: Yes - keep dogs on lead
Toilets: There are permanent port-a-loos installed at the Letterkeen Trail Head
When was I here: July 2026
External links:

The Letterkeen Trailhead is somewhere I’ve visited many times; most notably, when walking the Western Way back in 2018 (with extremely bruised soles and skin that had been eaten alive by the intense midgies that Mayo is infamous for) and last year in March 2025 to walk the Bangor Trail with my friend Pauline.

To come back and film some of the day hikes that the NPWS have developed has been on my to-do list for far too long. And so on a mid-July morning, I pulled into an almost-empty trail head car park. My main fear as I opened the van door was the already mentioned munching insects. However the mild threat of rain that hung over the area seemed to be keeping the worst away, and so I began to pack my bag quickly and get on trail.

The route is listed as 12km on all the signage, but I think it’s closer to 10.5km. However, if it’s your first time visiting the park, it’s worth budgeting some extra walking in your legs in case you see view points you want to explore. The Letterkeen Loop is the longest of the four looped walks that leave the main car park.

At the trailhead there are also permanent port-a-loos, and the Brogan Carroll bothy. This is the first true “bothy” I ever experienced in Ireland, and as far as I’m aware, was the first one to be renovated/created. It’s a simple, single stone room with a map of the park, a notice board with shuttle bus details and other things worth noting for walkers passing through. The old famine cottage was renovated by Mayo County Council and An Taisce thanks to donations by two Irish-Americans, John Brogan and Barry Carroll.

All the trails here are way-marked in one direction. Beforehand I would’ve said I’m not a fan of this idea - but it means that your experience of the park feels more empty than it might be. If you’re all walking in the same direction, your only chance to overlap is when someone takes a long enough break.

So as I set off on the path out of the car park and over the wooden bridge, I was pretty much alone. The path meanders around some gorse and along the riverside, narrow enough that it feels like it gets more sheep traffic than human. The river gully is deep, and in summer the ferns stand tall along the banks.

After maybe a kilometre, the trail makes its way from the twisting riverbanks and widens into a stony path. At the 1.5km mark, blue arrows point into the forest, marking the turn off for the 5km Bothy Loop. There is an imperceptible uphill to this valley, and as you look ahead and see the small rise ahead, you can see the trail cut across the top of it.

This climb feels a little more serious, but is still pleasant and gives great views back down the valley. Along this stretch you’ll also come across weathered way-markers from the Bangor Trail - the little green walking man almost consumed by the grey lichens.

After you’ve passed the 4km mark, you’ll encounter another turn off to the right with a red way-marker: this is the Lough Avoher Loop. If the climb you just did was as much climbing as you’re able for today, take this turn off.

Only a few hundred meters ahead is the Lough Avoher Shelter. This is one of two such Adirondack Shelters in the National Park. Mountain Meitheal (Ireland’s volunteer trail building organisation) adopted this style of shelter and have built several around the country along different trails (learn more here). I love these little huts, and had planned for this to be my lunch break. Arriving in the height of the summer season, there was more rubbish left behind than I’ve previously seen, but not terribly mistreated. Ten days later I was back with a group, and we removed what was there. Overall, I feel like the people who visit this area respect the Leave No Trace or “Pack it in, Pack it out” mentality, because it’s a little harder to get here than most places, and fewer people know it exists.

Leaving the shelter, the trail consistently climbs. Quite quickly, the tree line changes from being a tall presence hugging the path, to swishing branches below. The lake of Lough Avoher peeps through the branches. The trail here actually hugs the park boundary, although you’d have no idea apart from the line drawn on a map. For the 2km after the shelter, the ground is a little more boggy than before, and the trail dips in and out of the forest.

Soon, the path comes to the highest point of the loop, a 311m spot height with no name that I know of. The views all around are beautiful, even on the hazy day that I was there filming. Descending from here, there is a more substantial forest section. There are some fallen trees inside the forest which look a little dramatic, but overall it’s still very passable. This section can also be muddy and slippy.

Popping out of the other end of the forest, the little ridge line of Aroher Hill feels almost tall and imposing ahead of you. But the trail turns left, and brings you down onto the easy-going forestry track that the Western Way also follows, back to the Letterkeen trailhead. On the way you’ll pass other designated camping locations, an etherial elk*, and the steady flow of water once more.

* Tenaya is a life-sized willow sculpture of an Irish Elk by artist Brendan Farren. The Irish Elk, Megaloceros giganteus, was a species of giant prehistoric deer that it is thought to have gone extinct some 8000 years ago due to human hunting and the changing climate.

The sculpture was commissioned by the National Parks & Wildlife Service to commemorate the twinning of Wild Nephin National Park with Yosemite National Park in May 2024, and installed along the Letterkeen Looped walk in Wild Nephin. It is named after Tenaya, the last leader of the Ahwahnechee native people in the Yosemite Valley.