Martello towers sprang up all over the coastline in the nineteenth century. The early towers were originally built to defend the country from Napoleonic invasion.
Such towers were two-storey defensive forts, about 12m high and with walls 2½m thick.
Entry was by ladder to a door about 3m from the base, above which was a slotted platform that allowed for downward fire on attackers by defenders.
The flat roof had a high parapet and a raised platform in the centre, with a pivot for a cannon that would traverse a 360° arc.
Very effective, in theory.
All in all, a desirable residence, especially since Napoleon did not hove to off the Irish coast at all.
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