Coosaun Lough – The Wishing Lake of the Gap of Dunloe

Overview

Coosaun Lough sits at the northern tip of the Gap of Dunloe, a striking U‑shaped valley that separates the MacGillycuddy’s Reeks to the west from the Purple Mountain Group to the east. It is the first of five corrie lakes that the River Loe threads through – Coosaun, Black Lake, Cushnavally Lake, Auger Lake and Black Lough – each mirroring the rugged Old Red Sandstone cliffs that line the road. The lake’s tranquil surface is framed by the low stone Wishing Bridge, a favourite photo‑op for visitors travelling the Ring of Kerry or exploring Killarney National Park.

History & Geology

The name Coosaun derives from the Irish Cois Abhainn – “by the river” – an apt description for a lake both fed and drained by the River Loe. The Gap of Dunloe was gouged out about 25 000 years ago when a massive glacier broke through the Black Valley, leaving a series of deep depressions that later filled with melt‑water to become today’s lakes. The Irish name Dunloe (Dún Lóich) means “the fort of Lóich”, a nod to an ancient chieftain recorded in the Annals of Clonmacnois. Local legend holds that the stone bridge linking Coosaun Lough to Black Lake was built in the 19th century and that any wish whispered there will be granted – a story that still draws hopeful visitors.

What to See & Do

• Wishing Bridge – Pause on the historic stone bridge, whisper a wish and capture the mirror‑like reflections of the lake and surrounding cliffs.
• Short Walk from Kate Kearney’s Cottage – A well‑marked 1.6 mi (2.6 km) out‑and‑back trail (≈140 ft ascent) leads from the cottage’s car park to the bridge and back in about 30 minutes; ideal for families and time‑pressed travellers.
• Photography & Birdwatching – Early morning light turns the water gold, while swans, ducks and occasional white‑tailed eagles glide overhead.
• Climbing & Bouldering at Brennan’s Leap – The western shore hosts the crag known as Brennan’s Leap, offering over 100 routes from V‑Diff to E5 and ranking among Ireland’s top five bouldering sites.
• Boat Connections – From Ross Castle, a boat service stops at Lord Brandon’s Cottage, giving a unique water‑borne perspective of Coosaun Lough and the neighbouring lakes.
• Cushnavally Lake Scenic Lay‑by – Pull over at the designated lay‑by to admire the dark, glassy water framed by the Reeks; sunrise shots are especially spectacular.
• Walking to Cushnavally Lake – A gentle 1 km (0.6 mi) walk from Kate Kearney’s Cottage takes 15‑20 minutes. For the ambitious, the full 11 km Gap walk passes directly beside the lake, offering a peaceful pause before continuing toward the head of the Gap.
• Jaunting‑Car Rides – Traditional horse‑drawn carriages depart from Kate Kearney’s Cottage, following the road past both Coosaun and Cushnavally Lakes. Many tours combine the jaunting‑car with the Ross Castle ↔ Lord Brandon’s Cottage boat transfer for a complete water‑and‑land experience.

Getting There

Coosaun Lough is most easily reached via the car park at Kate Kearney’s Cottage, about 7.75 mi (12.5 km) from Killarney. Free on‑site parking is available, as well as public toilets. Regular shuttles run from the Killarney Tourist Office to Ross Castle (9:45 am, 11:45 am, 4:20 pm, €3) and to the Gap of Dunloe (hourly from 9:00 am, €5). For a scenic alternative, hop on a jaunting‑car from the cottage – rides typically last 1.5‑2 hours each way and can be combined with the Ross Castle‑Lord Brandon’s Cottage boat service (€25, advance booking recommended). Bike hire is also offered locally for those who prefer to cycle the valley.

Practical Information

Tip: Arrive early in the day to beat the crowds, secure a boat slot, and catch the sunrise over the lakes for unforgettable photographs.