A Martello-like tower was built on Achill Island, according to local memory during the Napoleonic Wars. It is square rather than round, unlike the traditional Martello tower. This tower is known locally as the Gabhla Fhranca ("French Tower") or the Napoleonic Tower. It is marked on an 1838 Ordnance Survey chart and denoted "Signal Tower", suggesting it was used with a series of other stations for communication. The tower's position offers a view of the sea both to the north and south of the island and is therefore well-suited for that purpose. By the 1830s the tower was described as a "watch-house of the coast-guard."
