Studies of the landscape beneath the waters of the Firth have revealed that the visible surface of Inchgarvie is only the top of a larger 'crag and tail' structure, similar in structure to Edinburgh Castle and the Royal Mile, created by glacial action.
From early days, this rocky islet, set in the midst of the waters of the Forth, had been regarded as of strategic importance owing to its situation.
Athelstaneford is a beautiful little village in East Lothian, nestling in the Garleton Hills, a mile or so from Haddington, the main town of the county. It is here that it is claimed that the origins of the Scots flag, the Saltire of Scotland, were occasioned by the results of a famous battle. Legend has it that a certain Saxon/Anglic King or Prince, Athelstan, was in East Lothian at the head of a large army, when he came across an army of Scots/Picts led by King Hungas (variants Onuist, Hungus or Angus) Mac Fergusa, King of the Picts in Modern Scotland from 820 – 834 AD. Being surrounded, King Angus prayed to St Andrew and just before the battle, a saltire appeared in the sky formed by white clouds against a blue background. This represented the shape of the cross on which Andrew had been crucified and seemed a sign from above that the Scots/Picts would prevail that day. It gave added strength and purpose to Angus and his men and a great victory followed. Ever after, the Scots/Picts showed a great devotion to St Andrew and the Saltire became Scotland’s National flag and Andrew their Patron Saint.
Athelstan’s head was cut off and displayed on top of a long pole on the little island of Inchgarvie, in the Firth of Forth, where King Hungas stopped, on returning to his kingdom North of the Forth.
It was with a view to preventing the devastations of Dutch and English pirates, that James 1V, in 1491, granted the Island of Inchgarvie to John Dundas of Dundas, with permission to build a fort on the rocky islet and levy 6 pence duty on passing ships, for protection from Pirates.
He was to surround the structure with stone walls to fortify and strengthen it and defend it with moats, iron gates, battlements, machicolations-(A projecting gallery at the top of a castle wall, supported by a row of corbels and
having openings in the floor through which stones and boiling liquids could be dropped on attackers.),
crenels- (gaps on ramparts through which arrows could be fired) and skowlaris and with all other and sundry munitions and defences. The building was to be adorned with warlike and defensive ornaments and a constable, warden, keeper of the prison, guards, porters and other officers necessary were to be established within its walls. The fortifications were not complete however until more than 20 years later.
The King did not live to see the fort completed, for the building operations seem to have been interrupted by the death of John Dundas in 1495, and not until after the Battle of Flodden was the fortification finished.
On 8 March 1514, Margaret the widow of William Dundas of Dundas undertook the completion of the fortress that James IV and her father-in-law had begun building on Inchgarvie island.
Since those days until the present day the barren rock of inchgarvie has remained as a strategic point in the defences of the forth.
Between 1519 and 1671, the castle was used as a prison.
Another use for Inchgarvie in 1580, was to house recovering plague victims.
From 1650 to 1651 , as Oliver Cromwell's Army marched North, Inchgarvie was occupied by the Royalists who built a Fort around the castle and used it to defend the Forth against Cromwell. In 1651 Inchgarvie resisted many attacks by Cromwell's flotilla but after the Battle of Inverkeithing and the defeat of the Royalists, supplies to Inchgarvie were cut off, forcing surrender. In 1654, Dunfermline Minister, Mr Kay, was imprisoned by Cromwell's men, for praying for the King! Inchgarvie continued to be used as a prison until 1671, when it was replaced in that task by the Bass Rock.
In 1779 Inchgarvie was armed with 4 - 24 pounders to protect shipping from pirates such as John Paul Jones, an American Naval Commander who harassed British ships from a base in the Forth. A few years later canons were put on the battery hill in view under threat of possible invasion from France. These fortifications were never used in anger.
During the Napoleonic period, the threat from the sea meant in 1806 the Fort was repaired and gun batteries were created, then mounted with cannons.
Inchgarvie was purchased by the Forth Bridge company for £4,300 for use as a base for the new bridge. The presence of Inchgarvie Island enabled the central cantilever to be based upon a solid foundation. The island, due to its proximity to the bridge, was also used as a construction office for the bridge, as well as accommodation for its workers within the re-roofed castle buildings. Some of the stone from the former castle was used to help build the caissons of the Forth Bridge.
During World War 1 Inchgarvie was garrisoned by the Royal Garrison Artillery
One sad incident involving Inchgarvie Island was reported in the Scotsman on 19th March 1915. Artillery Man Accidently Killed at Queensferry:
It was reported at headquarters yesterday that Corporal John Thomson, No 3 Company, Forth RGA had been found dead that morning on Inchgarvie. While going on duty he had evidently accidently fallen down the steps leading from the Forth Bridge to the island.
Corporal John Thomson No: 1012, of 3rd Company, Royal Garrison Artillery, was born c1887 in Kirkwall, Rousay, Orkney. His parents were William, a Marine Engineer, and Mary Thomson MS Reid. He enlisted in 1908 in Edinburgh aged 21. His Home address was 16 Hawthornbank Place, Leith and he was unmarried. At the time of enlisting, he was in 1st Edinburgh City Royal Garrison Artillery Volunteers.
He died on 17th March 1915 aged 28 at approx. 11pm, on Inchgarvie Island, from injuries caused by a fall from a height. The informant was Captain Miller of Forth RGA, Inchgarvie, North Queensferry.
Letters between RGA Records Office, Dover, and Officer in Charge, No3 Co. Forth RGA, Inchgarvie, North Queensferry, on request by the Pensions Department, show investigation regarding a previously reported insecure hand rail at the stairs. No records of this seem to exist and John's Service Records show no resolution.
His death was registered in Inverkeithing and he is buried in Grave Ref: B1. 964, Edinburgh Warriston Cemetery.
In World War 2, Inchgarvie was garrisoned by the Royal Artillery, and an anti-aircraft battery was installed. As such, the remains of the castle are now incorporated into the concrete defences.
Inchgarvie was subsequently neglected and it's stones used by builders for both sides of the river.
Local people have said they grew vegetables on the Island as they sailed up and down in their little boats.