BUILT in the wake of the Battle of Culloden as a base for government troops in the rebellious highlands, Fort George is said to be the finest example of 18th century military engineering in the British Isles.

Jutting out into the Moray Firth, it was built on a monumental scale and designed to be impregnable to an attacking army.

Using the latest technology of the time, it is laid out in such a way as any approaching force is covered by heavy guns with every angle said to be open to cannon fire from the defenders.

More than two-decades in the making, the fort was completed long after the Jacobite insurrection had fizzled out, yet remains a powerful symbol to any would-be rebels and became a recruiting base and training camp for the rapidly expanding British Army.

It remains in army hands today, and is currently the home of the Black Watch 3rd Battalion, The Royal Regiment of Scotland.

Yet despite being impregnable to man-made attack, the fort is losing its battle with the elements and faces a tough fight in the coming decades.

The HES climate change assessment rates the building at very high risk from coastal erosion, at high risk from groundwater flooding and there is a medium risk it will slide into the sea as the soil, upon which its walls rest, collapses.

It’s very position on the shore is part of the danger – and there are signs the coastal defences are being washed away by seawater. Rock armour has been installed on the exposed, north-facing side, in a project carried out in partnership with the Army, to hold back the tide but heritage bosses will have to remain vigilant.

Sea levels are predicted to rise by in the coming decades, possibly submerging part of the forts walls.