Overview
Mulroy Bay (Irish: Cuan na Mhaoil Ruaidh, ‘bay of the red current’) is a 12 km sea loch on Donegal’s north coast, and its character is set by the tide. A narrow entrance opens onto a winding 10 km channel pinched by three narrows only 100-150 m across, where currents run at 3-5 knots. Past them lies the Broad Water, an 8 km shallow lough scattered with rocky islets. The name comes from the reddish cast the water takes on in winter.
Villages on the shore – Milford, Kerrykeel and Cranford – have traditional pubs, craft shops and places to stay. Hills, sandy beaches and woodland ring the water.
Set in the sheltered inner bay is Red Island (Oileán Ruaidh), a low island that turns deep russet in winter. A tidal causeway reaches it, and it is a designated Discovery Point on the Wild Atlantic Way and a seabird nesting site.
If you’ve only a few hours, drive the 35 km Mulroy Drive out of Milford for Fanad Lighthouse and Ballymastocker Bay, and time Red Island’s causeway walk for low tide.
History
The Irish name points to a long maritime past, when the bay was a route for fishing and trade and villages grew around small harbours and forges. Local lore still talks of the ‘Red Stream’ and the old forge sites around the shore.
Red Island’s earliest recorded name was Oileán na Bhreighe, ‘island of the prisoners’, which hints at a refuge or place of confinement. In the 19th century English surveyors wrote it down as ‘Island Roy’, a phonetic take on Oileán Ruaidh; the modern Irish name reflects the island’s winter colour.
What to see and do
Mulroy Drive
The 35 km Mulroy Drive loops out of Milford, tying in the Atlantic Drive, Fanad Lighthouse, Ballymastocker Bay and the Knockalla Coast. Viewing points funded by Fáilte Ireland frame the sea-inlet views and coves, and make good picnic and photo stops.
On the mainland
- Walking – the 7 km Colmcille Trail and the 1.5 km Woodquarter Forest Trail run through woodland and along the water past a 17th-century church.
- Water sports – kayaking, including full-moon tours, with Eco Atlantic Adventures, plus canoeing, paddle-boarding and deep-sea fishing from Woodquarter and other launch points.
- Diving – Mevagh Dive Centre, a 5-star PADI facility, runs guided dives on local wrecks from as shallow as 10 m and has a heated indoor pool.
- Cycling, mountain biking and horse riding – Mulroy Drive’s gentle gradients suit road cyclists and families; rougher tracks near Kerrykeel suit mountain bikers; Ashtree Riding Stables run guided rides across the hills.
- Stargazing – low light pollution around Kerrykeel makes for clear night skies.
Red Island
A short, well-marked path circles the island with uninterrupted views across Mulroy Bay to the Donegal coast, an easy walk that suits families. Its cliffs and scrub hold nesting gulls, terns and the odd puffin in summer, with otters and seals in the water around it. Signage at the causeway gives a brief overview and a QR code links to an audio guide.
Practical information
- Access – Red Island is reached by a tidal causeway from the mainland near Carrigart, a low-tide crossing passable except around high tide. Check the tide first: the causeway is under water for several hours around high tide. Tables are at the Carrigart harbour office or online via Met Éireann.
- Facilities – the mainland villages have parking, public toilets, cafés and accommodation from B&Bs to self-catering cottages. There is nothing on the island, so carry water and food.
- Parking – free car parks in Milford and Carrigart, both a short walk from the Mulroy Drive trailhead and the Red Island causeway.
- Safety – wear sturdy footwear for the island’s uneven path. The currents are swift, fastest through the three narrows at 3-5 knots, so kayakers and divers should check the marine forecast before setting out.
- Weather – the Donegal coast changes fast; even in summer expect strong wind and rain, so pack waterproofs and layers. Early morning and late afternoon give the softest light and the calmest sea.
- Seasonality – the red water and island vegetation are most striking in winter; bird-watching peaks in summer.
Nearby
- Ballymastocker Bay (/ballymastocker-bay/) – a Blue Flag beach of white sand and clear water, a short drive north.
- Doe Castle – a 16th-century fortress on a Sheephaven Bay peninsula, with a bawn wall and keep, 15 km west.
- Broad Water – the shallow southern lough of Mulroy Bay, good for kayaking and bird-watching.