On the northern tip of Inch Island, where rocky ground meets the waters of Lough Swilly, stand the weathered remains of a military fortification that once formed part of Britain's coastal defences against Napoleon. Inch Fort tells the story of invasion fears, imperial strategy, and the changing nature of warfare across more than a century.
Why Lough Swilly Needed Defending
The story of Inch Fort begins not with its construction, but with a naval battle fought in October 1798.
On 12th October that year, a French fleet carrying the revolutionary leader Theobald Wolfe Tone and 3,000 troops entered Lough Swilly, intending to support the Irish Rebellion. The French were unaware that the uprising had already been crushed. A British squadron intercepted them off Tory Island in what became known as the Battle of Tory Island.
The French flagship Hoche was captured at Buncrana, and among the prisoners was Wolfe Tone himself. He was court-martialled and sentenced to death, though he died from self-inflicted wounds before the sentence could be carried out.
The battle exposed a vulnerability. Lough Swilly's deep waters, sheltered anchorage, and proximity to Derry made it an ideal landing point for any invasion fleet. If the French had arrived before the rebellion's defeat, history might have unfolded very differently.
The Napoleonic Forts
With Napoleon now dominating Europe and the threat of invasion ever-present, the British government acted. Between 1800 and 1820, a network of fortifications was constructed around Lough Swilly, designed so that any hostile fleet would face crossfire from both shores.
The defensive network included:
- Fort Dunree (east shore) - the principal fortification
- Ned's Point Battery (Buncrana)
- Knockalla Fort (west shore)
- Rathmullan Battery (west shore)
- Macamish Point (west shore)
- Inch Fort (on Inch Island, commanding the upper lough)
Signal towers at Fanad Head and Malin Head completed the early warning system.
Construction of Inch Fort (1812-1813)
Inch Fort was built between 1812 and 1813 on a rocky promontory known as the Down of Inch. The position offered uninterrupted views of the upper reaches of Lough Swilly, the western shore beyond Rathmullan, and the eastern shore beyond Buncrana.
The fort was designed by Captain William Smith, whose original sketches survive in the archives of Trinity College Dublin. It's likely the fort was built on the site of an earlier fortification from antiquity—the strategic value of this position had been recognised for centuries.
Original Design
The Napoleonic-era fort featured:
- Nine gun positions: six in an open battery and three in a blockhouse (likely a Martello-style tower)
- Armament: Three 5.5-inch howitzers and six 24-pounder cannon
- Designed capacity: 2 officers, 5 bombardiers, and 80 gunners
The howitzers were positioned for high-trajectory fire, designed to penetrate the decks of enemy ships. The heavier 24-pounder cannon provided longer range for engaging vessels at distance.
The guns were most likely Blomefield pattern cannon—the standard British artillery of the Napoleonic Wars. As military historian Dr A.R. Collins noted: "The Napoleonic Wars were fought and won with Blomefield guns and carronades."
A Fort That Never Fired in Anger
Napoleon's defeat at Waterloo in 1815 ended the invasion threat, and the Lough Swilly defences were neglected. Inch Fort, which had never reached its full garrison strength, was progressively scaled down.
- By 1823: The garrison had been reduced to just 8 men
- By mid-19th century: Only one invalided soldier remained to maintain the position
For decades, the fort stood largely abandoned, its guns silent, its purpose seemingly obsolete.
Victorian Rearmament (1895-1897)
In the 1880s, renewed concerns about coastal defence—this time against modern ironclad warships—led to a reassessment of Britain's fortifications. Lough Swilly, still a strategically important deep-water anchorage, was included in the upgrade programme.
Work on Inch Fort commenced in 1895 and was completed in 1897. The contract was awarded to Camel and Sons of Belfast, who employed local workers alongside their own men. According to the DĂşchas Schools' Collection, the local workforce included Joe Durnin, James Sweeny, Alic Craig, James Hardy, and John Thomason, with a Mr Beard serving as foreman.
The remodelling was extensive:
- The original Napoleonic blockhouse was largely demolished, its stone reused to build a new Guard House
- New magazines and defensive embrasures were constructed
- A small barrack complex was added, along with stores, latrines, and a cookhouse
- Two 6-inch guns on hydropneumatic disappearing carriages replaced the old smoothbore cannon
The total cost was £6,279 3s 6d—approximately €930,000 in today's money.
The Disappearing Guns
The new 6-inch guns represented the cutting edge of 1890s military technology. Mounted on hydropneumatic carriages, they could be loaded in the safety of a pit, then raised briefly to fire before the recoil mechanism lowered them back out of sight. This made them extremely difficult for enemy ships to target—a crucial advantage in the age of accurate naval gunnery.
These weapons could engage targets at ranges far beyond anything the Napoleonic-era cannon could achieve.
The 1901 Census
The 1901 Census provides a snapshot of life at the fort during this period. The garrison consisted of:
- One Bombardier
- Four Gunners
- All serving with the Royal Garrison Artillery
The census also recorded bricklayers lodging at nearby Grange, suggesting construction and maintenance work was ongoing.
Soldiers did not live permanently at Inch Fort. According to local memory preserved in the Schools' Collection, they would "camp for the night" when their ships arrived, rather than maintaining a continuous presence.
Abandonment and Later History
In 1905, the Owen Committee reviewed the armaments of Britain's home ports. Inch Fort's guns were deemed surplus to requirements, and the fort was disarmed and abandoned.
The fort's military story wasn't quite over, however:
- 1921: The British garrison departed as part of the withdrawal from the newly independent Irish Free State
- 1922: Republican forces briefly occupied the fort during the Civil War
After this, the fort passed into private ownership and was left to the elements.
What Remains Today
Inch Fort today is a striking ruin on private land. The site preserves:
- The two 6-inch gun positions from the 1890s rearmament
- The associated magazines (ammunition storage)
- Remnants of the Victorian-era barrack buildings
- Parts of the original Napoleonic-era earthworks
The original Martello-style blockhouse was largely demolished during the 1890s reconstruction, though some foundations may survive beneath later structures.
The fort is not open to the public as it sits on private property. However, it can be viewed from the water or from certain vantage points on the island. The CINE Project obtained special permission to document and photograph the site for their heritage archive.
Inch Fort in Context
Inch Fort was one link in a chain of defences that protected one of Ireland's most strategic waterways. Today, Fort Dunree on the eastern shore has been restored as a military museum and offers visitors the chance to explore a similar fortification in detail. The remains at Knockalla, Rathmullan, and Macamish can also still be traced.
Together, these forts tell the story of over a century of military history—from the revolutionary turmoil of the 1790s, through the long peace of the Victorian era, to the political upheavals of the early twentieth century.
Inch Fort may never have fired a shot in anger, but its silent guns and crumbling walls speak eloquently of the fears and ambitions of the age that built them.
Sources
- Inch Heritage / CINE Project - Comprehensive timeline of Inch Island history
- DĂşchas Schools' Collection - Local folklore collected in the 1930s
- Military History Wiki - Technical details on armament and construction
- Battle of Tory Island - Context for the fort's construction
- 1901 Census of Ireland - Garrison records
Image: Inch Fort ruins © Kenneth Allen / Geograph (CC BY-SA 2.0)
For more on Inch Island's rich history, see our History of Inch Island guide.