Overview
Perched on a small, rocky island at the heart of Mulroy Bay, Moross Castle is a striking fragment of a 16th‑century tower house. Only the southwest corner of the original structure remains, rising two storeys above the sea‑sprayed cliffs. A short 45 m causeway links the island to the mainland, giving the ruin an isolated feel while keeping it easily reachable on foot or by bike. The site is a favourite stop for drivers on the Mulroy Drive scenic route and for walkers exploring the coastal trails around Milford.
History
Moross Castle was built in 1532 by Turlogh Mac Suibhne, a member of the powerful Mac Sweeney (Mac Suibhne) clan that migrated from Scotland after the Battle of Bannockburn. The clan had already established a presence in Fanad during the 14th century, with earlier family strongholds at Rathmullan (1516) and a Carmelite priory built by Turlogh’s aunt, Maire, still visible today.
In 1610 the castle was granted to Henry Vaughan. A 1622 survey described the ruin as an “old Irish castle” whose walls had been partially repaired, and noted a thatched birch‑timber roof added by Arthur Terry, Vaughan’s assignee – a rare post‑medieval roof for a stone tower house. The same report mentions a stone‑only court, five feet high, built by Terry without mortar. By the mid‑17th century the castle had fallen into disrepair as the Mac Sweeneys’ fortunes shifted during the Cromwellian and Williamite wars.
The surviving SW corner, built of rubble set in a coarse sea‑sand mortar, still shows the original ashlar bond holes. Architectural features such as a mural passage in the west wall, a splayed ingoing, and the remains of a murder‑hole shaft on the north side reveal the defensive character of the tower house. A later stone‑facing on the north cliff likely underpinned the NW corner against Atlantic winds.
What to See & Do
- The Ruined Corner – Walk the 45 m causeway and stand beside the two‑storey stone fragment. The coarse mortar and ashlar bond holes give a tactile sense of medieval construction.
- Mural Passage – Peek into the 1.4 m‑high passage cut into the ground‑floor west wall; it hints at the original interior circulation.
- Cliff‑Top Vistas – From the island’s edge you can gaze across Mulroy Bay to Umricam, Doocarrick, Milltown, Lower Ballyheerin and the twin islands known locally as The Big Isle and The Wee Isle. Sunrises and sunsets create striking photographic opportunities.
- Historical Poetry – The 19th‑century poem “Winding Mulroy Bay” by Hugh Friel mentions Moross Castle, adding a literary dimension to the visit.
- Mulroy Drive Walk & Cycle Route – The ruin forms a waypoint on the officially sign‑posted Mulroy Drive walking and cycling routes (7 km Colmcille Trail, 1.5 km Woodquarter Forest Trail). Both routes pass historic sites such as a 17th‑century church and standing stones.
- Nearby Activities – After exploring the castle, consider a guided tour of Fanad Lighthouse, a moon‑light kayak with Eco Atlantic Adventures in Woodquarter Bay, or a dive at Mevagh Dive Centre – all highlighted on the Mulroy Drive guide.
Mulroy Drive – Walking & Cycling Routes
The Mulroy Drive initiative promotes a 35 km coastal loop that links Fanad Lighthouse, Ballymastocker Bay, Rosguill Peninsula and a series of historic way‑points. Moross Castle is listed as one of the key stops on the route. The two main trails that pass the ruin are:
- Colmcille Trail – a 7 km walk that follows the shoreline from Milford, weaving through woodland, past a 17th‑century church and several standing stones before reaching the castle.
- Woodquarter Forest Trail – a shorter 1.5 km loop that climbs through mixed forest, offering views of Gull Island and Inishyweel in the bay below.
Both routes are sign‑posted, free to use and suitable for most fitness levels. Cyclists can follow the low‑traffic back‑roads that connect the trailheads, making Moross Castle a popular photo stop on a scenic bike ride.
Photography & Wildlife
The ruin’s position on a low‑lying causeway means it catches the first light of sunrise and the golden glow of sunset – ideal for landscape photography. For the best contrast, visit on a clear day when the sea is calm; the reflected sky adds depth to the stonework. Early morning or late evening also brings a chance to spot seabirds such as gulls, razorbills and, occasionally, puffins that hunt along the cliffs.
Seasonal & Practical Tips
- Tides – The causeway is exposed at low tide but can be wet or briefly submerged during extreme high‑water events. Check the Irish Marine Forecast or local tide tables before planning a early‑morning or late‑evening visit.
- Dog policy – Dogs are welcome on the causeway and around the ruin but must be kept on a leash for safety near the cliff edges.
- Weather – The site is exposed to Atlantic winds; a wind‑proof jacket and sturdy footwear are advisable year‑round.
- Accessibility – The causeway is uneven and the ruin’s stonework uneven; it is not wheelchair‑friendly.
- Facilities – No on‑site amenities. Public toilets, cafés and a small shop are available in Ballina and Milford.
Getting There & Parking
The most common approach is via the L10921 road at Ballina, roughly halfway between Rossnakill and Tamney. The road is narrow; we recommend parking in the designated lay‑by at Ballina (free, with space for cars and bicycles). From the car park follow the signed lane for about a mile to the stone‑slab causeway that leads onto the island. An alternative parking point is the small lot at the edge of Milford, which is a short walk further along the Mulroy Drive route.
Visitor Tips & Safety
- Tides – The causeway is exposed at low tide but can be wet or briefly submerged at extreme high‑water events. Check local tide tables if you plan a visit early morning or late evening.
- Accessibility – The causeway is uneven and the ruin’s stonework is uneven; it is not wheelchair‑friendly. Sturdy footwear is advised.
- Family‑friendly – Children enjoy the open space and the chance to explore a real castle ruin, but supervise them closely near the cliff edge.
- Weather – The site is exposed to Atlantic winds; a wind‑proof jacket is recommended year‑round.
- Facilities – No on‑site amenities. Public toilets, cafés and a small shop are available in Ballina and Milford.
Practical Information
- Opening – Open year‑round, free of charge.
- Contact – For the latest access notices, the Mulroy Drive office can be reached at +353 74 915 3736 (same number as listed). Email: donegalmulroydrive@yahoo.com.
- Safety – Watch for loose stones and steep drops; stay on the marked path.
Nearby Attractions
While in the area, you can:
- Visit Fanad Lighthouse (a Wild Atlantic Way signature point) – guided tours run from May to September.
- Join a moon‑light kayaking session with Eco Atlantic Adventures in Woodquarter Bay.
- Dive at Mevagh Dive Centre, exploring local shipwrecks.
- Explore the historic Doe Castle across Sheephaven Bay, another Mac Sweeney stronghold.
Moross Castle may be a fragment, but its stone walls echo the power and resilience of the Mac Sweeney clan and the ever‑changing tides of Donegal’s history. Whether you are a history enthusiast, a photographer, or simply a lover of rugged coastal scenery, the ruin offers a uniquely atmospheric glimpse into Ireland’s medieval past.