Overview
Lough Swilly is a glacial sea inlet that splits the Inishowen Peninsula from the Fanad Peninsula in north Donegal. It is often grouped with Carlingford Lough and Killary Harbour as one of Ireland’s fjord-like inlets. Its Irish name, Loch Súilí, means ‘lake of eyes’, though ‘lake of shadows’ is the version you’ll hear locally.
The shelter and depth made it a naval prize. A ring of Napoleonic forts still guards the shore, a gold-laden liner lies wrecked off its mouth, and it was from here, at Rathmullan, that Hugh O’Neill and Rory O’Donnell sailed into exile in the Flight of the Earls in 1607.
A landscape shaped by history
The human story here runs deep. Archaeologists have found shell middens dating to around 7000 BC, and the Iron Age fort of Grianán Ailigh still crowns the hill above the southern shore. The lough’s strategic weight showed itself in 1607, when the Flight of the Earls left from Rathmullan, ending the old Gaelic order.
By the Napoleonic era, the lough’s depth and shelter made it a prized anchorage. Between about 1800 and 1820 the British built a ring of defences, six Martello towers and several larger forts, among them Fort Dunree, Lenan Head, Ned’s Point, Inch Fort, Knockalla and Macamish Point, to keep the French out. The sea took its own toll: the frigate HMS Saldanha was wrecked here on 4 December 1811 with the loss of all 253 crew, some 200 of whom washed ashore. The lough later held part of the Grand Fleet in the First World War and stayed a British Treaty Port until 1938, when Fort Dunree was handed over to the Irish state.
What to see & do
Wildlife & birdwatching
The Inch Levels Wildfowl Reserve lies on the eastern side of the lough, south of Buncrana. Its wetlands support wintering swans and geese. Use the reserve’s public paths and hides and leave feeding birds undisturbed. Out on the lough itself, grey seals, bottlenose dolphins and harbour porpoises are sometimes reported, especially on calm mornings.
Historic forts & museums
- Fort Dunree – a managed museum and coastal site on the Inishowen shore. Check the operator for opening and use the visitor paths.
- Lenan Head Fort – one of the larger coastal forts built to guard the entrance, later fitted with heavy guns. The setting and the view across the mouth are the draw.
- Inch Fort and Ned’s Point – ruins that trace coastal defence from the early 1800s through the World Wars.
The SS Laurentic
Off the mouth of the lough lies the wreck of the SS Laurentic, a British liner requisitioned as a troopship and sunk by a German mine in January 1917 while carrying a cargo of gold ingots. Most of the gold was recovered in a long salvage operation. The wreck lies far below the surface and is not a casual dive; this is a story to read about rather than something to plan around.
Fanad Head and the ferry
At the mouth of the lough, check Fanad Head Lighthouse for guided visits. If you plan to cross between Buncrana and Rathmullan, check the ferry operator for sailing dates before you travel.
Practical information
- Getting there – the lough is reached from Buncrana, Rathmullan and Portsalon, the main gateways. Check bus services to Derry and Letterkenny with the operator before travelling.
- Best time to visit – winter for the birds, though check the reserve before you go.
- Safety – the lough is tidal and currents can be strong, especially through the narrows and around the island channels. Keep to public paths at the forts and reserve.
Nearby attractions
- Ballymastocker Bay – a wide golden strand at Portsalon, good for a walk after a drive round the Fanad shore.
- Grianán of Aileach – the stone ring fort on the hill above the southern shore, with views over both Lough Swilly and Lough Foyle.
- Fanad Head Lighthouse – at the tip of the Fanad peninsula, on the western side of the lough’s entrance.
For a day of it, start at Fort Dunree for the museum and the view down the lough, then drive round to Portsalon for the beach – and pack a waterproof whatever the forecast says.