Knockalla Fort is one of several Napoleonic batteries built along the shores of Lough Swilly in county Donegal, to defend the north west of Ireland. It was part of a scheme to fortify Lough Swilly and Lough Foyle against French Invasion during the Revolutionary and Napoleonic Wars and was completed between 1812 and 1813. On the other side of the Lough is Fort Dunree. The fort was built on the site of a temporary fortification first built in 1798.
It is triangular in shape with a tower on the landward salient angle. From the tower, the two walls of the fort, protected by a dry moat partly cut into the rock, lead down to the edge of steep rocky cliffs, where there are batteries on two levels. The lower battery with seven gun emplacements, originally mounted French 42 Pounder smooth bore guns on traversing platforms. The upper level contains barrack accommodation, magazine, casemates, entrance gateway and an upper battery for two 24 Pounder smooth bore guns on the northern flank of this level. The tower is quadrant-shaped in plan with corners rounded off and was armed with a 24 Pounder gun and a 5.5-inch howitzer.
After the end of the Napoleonic Wars the defences were neglected and not updated. By the 1860s the Fort was armed with an 18 Pounder gun and 5.5-inch howitzer in the tower. The upper battery had a 24 pounder gun. By this time the Fort was obsolete and was disarmed and abandoned by the military in the 1870s.
The fort remains substantially intact, and is now in use as a private residence.
References:Dryburgh Abbey on the banks of the River Tweed in the Scottish Borders was founded in 1150 in an agreement between Hugh de Morville, Constable of Scotland, and the Premonstratensian canons regular from Alnwick Abbey in Northumberland. The arrival of the canons along with their first abbot, Roger, took place in 1152.
It was burned by English troops in 1322, after which it was restored only to be again burned by Richard II in 1385, but it flourished in the fifteenth century. It was finally destroyed in 1544, briefly surviving until the Scottish Reformation, when it was given to the Earl of Mar by James VI of Scotland. It is now a designated scheduled monument and the surrounding landscape is included in the Inventory of Gardens and Designed Landscapes in Scotland.
David Erskine, 11th Earl of Buchan bought the land in 1786. Sir Walter Scott and Douglas Haig are buried in its grounds.