of a pair of Martello Towers built on either side of the narrow entrance
to Lough Foyle in the northwest of Ireland. These towers were build
around the coast of the British Isles to protect against an invasion
by Napoleon. The entrance to the Lough, while narrow, could not be
commanded by a cannon on just one side, hence the need for a pair
of towers. This tower is on the County Derry side and is viewed from
the County Donegal side of the entrance.