Fear of an invasion by Napoleon Bonaparte reached panic proportions among the authorities in Ireland and England in 1804 and was the reason Martello Towers were built, first in Ireland and then in England. Their purpose was to provide what were, in those days, ‘bombproof’ towers from which fire could be directed at ships of the hourly expected French invasion fleet. Martello Tower Sutton was the first Tower to be built in Dublin and is referred to in the annals as Tower No. 1.
The original Towers from the Napoleonic era are circular in shape, with 2-4 meter thick walls, which were made from solid stone that was all sourced locally. The entrance doorways of the towers are 3.0 metres from the ground which meant at the time access to the entrance was only made by a ladder. The ladder then could be removed to protect against an invader. They typically had a garrison of one officer and 15–25 men. Their round structure and thick walls of solid masonry made them resistant to cannon fire, while their height made them an ideal platform for a single heavy artillery piece, mounted on the flat roof and able to traverse, and hence fire, over a complete 360° circle.
The Towers never fired a cannonball in anger, as Napoleon never invaded Ireland or England. However, it is believed that the Towers acted as a deterrent, as Napoleon had every intention to invade England using Ireland as a “back door” bridgehead.
In total there were 50 Martello Towers built in Ireland, and 103 built in England. The function and purpose of the Towers in Ireland today differs from one to another. In Dublin while there are 21 Towers that remain standing many are derelict, some demolished, some are owned by government departments, and others are privately owned, some of which are habited and some uninhabited.
The cache is placed close to where another cache survived for 13 years, so I'm hoping to get the same longevity from this one! Please tuck it back in so as it's not peeking out.