Banagher Martello Tower, Banagher, Co. Galway

This one at Banagher looks instead at a river. It stands on the west bank of the Shannon, its tapered walls of ashlar limestone rising two storeys above the bridge crossing, and that inland position is what sets it apart from the coastal chain of towers built during the same anxious years. A river crossing, rather than a beach or harbour mouth, was judged worth defending in its own right.

The tower dates from around 1805, part of a wider programme of fortification thrown up across Britain and Ireland in response to the perceived threat of a Napoleonic invasion. The design, a squat, tapering drum with thick walls capable of deflecting cannon fire, had already proved itself in a British assault on a Corsican tower at Mortella Point some years earlier, and the name stuck as it was copied along vulnerable coastlines. Inland examples like this one are rarer, and this tower's job was specifically to cover the bridge at Banagher, a crossing point significant enough to warrant the same defensive treatment as a harbour. It stands close to Cromwell's Castle, an earlier fortification nearby, and together with the bridge the three structures form a group spanning different periods of the river's defence, each generation of engineers addressing the same strategic problem of controlling passage across the Shannon.

The building itself repays a slow look rather than a quick glance. The walls carry a projecting plinth course and cut limestone coping, with cast-iron rainwater goods still fitted. On the south side, a square-headed opening at first floor level has a sloping sill and projecting brackets to its east side, likely once used for hoisting supplies or equipment into the upper storey. Other openings on the north and south sides retain their original cast-iron grills. The tower is no longer in use, but its solid limestone construction has kept it standing largely intact, a plain and functional structure whose severity of design speaks to the urgency of the period that produced it.