18th & 19th Century Defences

In 1204, King John lost the Duchy of Normandy to the French Crown but retained the Channel Islands. Since that time, there has often been a need to defend the islands against the French and her allies.

Towards the end of the 18th century, the threat of possible attack and invasion increased again.

The American War of Independence began in 1775. Three years later France became an ally of America and declared war on Britain. It was feared that the French would seize the opportunity and attack and invade not only the Channel Islands but also Great Britain. Throughout the subsequent French Revolutionary (1792-1802) and Napoleonic Wars (1803-1815) the threat from France continued.

During this period, a comprehensive chain of defences were erected around the coast of Guernsey including forts, gun batteries, magazines, towers and watch houses. These fortifications were manned by regiments of the Guernsey Militia.

Forts

Several large forts were constructed, often on the sites of earlier fortifications. These were built to defend the large beaches on the north and west coasts. More...

Gun Batteries

At one time, there were over 60 gun batteries in operation around the island. They were constructed in strategic positions to protect the coastline from possible landings by the French. More...

Magazines

These small granite structures were built to store barrels of black powder for the cannons, usually on or close to gun batteries or forts. More...

Towers

15 loophole towers were built around the island between 1778 and 1779 to protect some of the islands most vulnerable beaches from potential invasion. More...

Watch-houses

These watch-houses were part of a chain of signaling and observation posts around the coast of Guernsey. The militia stationed at these positions had to raise the alarm if French ships were sighted. More...