Three people walking away from the camera on a forest path covered in fallen leaves.
Three hikers walk along a trail covered in autumn leaves at Annagh Lough Woods. Courtesy Failte Ireland

Annagh Lough

📍 Achill Island, Mayo

🏛️ Attraction

Last updated: 21 May 2026

Overview

Annagh Lough Woods sit on the exposed western fringe of Achill Island, County Mayo, where the Atlantic wind meets glacial stone. The woodland fringes Annagh Lough (also known locally as Lough Nakeeroge East), a small, sheltered basin resting just 15 m above sea level. This elevation makes it the lowest corrie lake in Ireland, a rare geological feature preserved at an unusually low altitude thanks to the moderating influence of the Gulf Stream. The surrounding terrain is a rugged mix of limestone outcrops, wind-scoured scrub, and pockets of planted woodland on the Curraun Peninsula, all framed by the sheer Atlantic face of Croaghaun.

A Landscape Shaped by Ice & Wind

The name corrie comes from the Scottish Gaelic coire, referring to the steep, amphitheatre-like hollows carved by glaciers during the last Ice Age. While most Irish corries sit high in mountain ranges, Annagh Lough’s low altitude is a direct result of post-glacial sea-level rise and coastal erosion that left the basin stranded just above the tide line.

The woods themselves are a blend of natural regeneration and 20th-century afforestation. Much of Achill remains open peatland and coastal scrub, but the Curraun Peninsula has seen decades of community-led and commercial planting. Today, the trail passes through a mix of conifers and native broadleaf species, including birch, hazel and ash, which have gradually established themselves in the sheltered hollows. A short distance from the lake, the landscape opens onto the machair grasslands near Keel. Derived from the Irish machaire (a level plain), machair is a rare coastal habitat formed by wind-blown sand mixing with shell debris and limestone. It supports a specialised community of wildflowers and is protected under EU directives.

Flora, Fauna & The Eagle Legacy

The microclimate created by the Gulf Stream and the shelter of Croaghaun allows Arctic-alpine plants to survive far lower than their typical range. Juniper (Juniperus communis) is the most visible, growing as low, gnarled shrubs across the limestone scree. In late spring and early summer, the surrounding heathland flushes with purple heather, bird’s-foot trefoil and wild thyme.

Birdlife thrives in this transitional zone between woodland, cliff and open coast. The Croaghaun cliffs attract red-billed choughs, whose chattering calls echo across the valley, while golden plovers wheel over the heather and peregrine falcons patrol the updrafts. During migration, Keel Lake acts as a staging post for barnacle geese and other waders.

The island’s very name may honour these raptors. One widely accepted origin for “Achill” is the Old Irish acaill, meaning “eagle”. Early records, including a 1235 reference in the Annals of Loch Ce as Eccuill (Eagle Island), point to a once-substantial population of white-tailed and golden eagles. The last confirmed sighting on Achill was in 1912, but the skies here remain active with falcons, buzzards and wintering merlins.

Walking & Exploration

The main route around Annagh Lough is a gentle, unmarked loop that follows the natural contours of the basin. The path is largely even, with occasional natural stone steps and muddy patches after heavy rain, making it suitable for casual walkers and families. The circuit takes roughly 45 minutes to an hour at a leisurely pace.

What to look for:

  • Juniper colonies clinging to limestone outcrops near the water’s edge
  • Native broadleaf regeneration where planted conifers give way to birch and hazel
  • Cliff views across to Croaghaun, where sea stacks and wave-cut notches mark the boundary between land and ocean
  • Machair grasslands a short walk south toward Keel, particularly vibrant in June and July

The trail is best enjoyed in the early morning or late afternoon when the light softens and bird activity peaks. There are no signposts or waymarks, so it helps to follow the main track circling the lake and note the position of Croaghaun to your west.

Practical Information

  • Opening & Admission: Open year-round. Free entry.
  • Parking: A small lay-by on the R319 provides parking for a handful of cars. Arrive early in summer to secure a spot.
  • Facilities: None on site. No toilets, cafés or waste bins. Carry out everything you bring in.
  • Accessibility: The route is mostly level but includes uneven ground, roots and natural steps. Not suitable for wheelchairs or pushchairs.
  • Dogs: Dogs are welcome but must be kept under close control, particularly near bird nesting sites and grazing land.
  • Getting there: From Westport, take the N59 toward Achill Sound, then turn onto the R319. Follow signs toward Keel; the woods and lake are signposted on the western approach.
  • Safety: The area is exposed to Atlantic weather. Winds can be sudden and strong, and cliff edges nearby are unstable. Stay on established tracks, check forecasts before heading out, and wear sturdy footwear.

Nearby Attractions

  • Croaghaun – The 600-m sea cliffs that dominate the western horizon, offering dramatic coastal walks and raptor-watching opportunities.
  • Keel – A quiet coastal village with traditional pubs, B&Bs and direct access to the protected machair grasslands.
  • Achill Sound – The island’s main hub, featuring Glendarary Woods, a historic harbour and regular ferry connections to the mainland.
  • Slievemore – Achill’s highest peak at 671 m, providing challenging hikes and 360-degree views across the Atlantic and Connemara.

Pack a light jacket and a pair of binoculars, and time your visit for the summer solstice when the long daylight hours allow you to explore the juniper-scattered slopes and catch the evening light catching the limestone ridges of Croaghaun.