Moville Lighthouse, Moville, Co. Donegal

Pile lighthouses, built on driven iron piles rather than solid masonry foundations, once marked several of Ireland's busiest channels, but only three survive today: this one, another at Dundalk, and a third at Cobh. Moville's example was the largest of the group, its iron-clad tower and canted polygonal roof rising to a light mounted on its own structural frame, with cantilevered walkways running up to the first and second levels, all held together on a lattice of legs planted directly in the estuary mud.

The light was erected in 1882 to guide vessels along the navigation channel from Derry down to the open sea, a route that carried enormous traffic through the second half of the nineteenth century as emigrant ships left for America and Australia. In its earliest years the lighthouse burned paraffin, and the keepers did not live on site at all; they lodged in Moville itself and rowed out to the structure each evening to tend the flame through the night, then rowed back at dawn. That arrangement gave way in 1912 to compressed gas cylinders, a system that could keep the light burning unattended for three months at a stretch, sparing the keepers their nightly crossing. The lighthouse has since been converted again, this time to solar power, continuing a pattern of quiet technological updates spanning well over a century.

Today the light stands 13 metres high, flashing once every two and a half seconds and visible for four miles, with a red sector trained on Moville Bank to warn shipping away from the shallows just inshore. It sits south of the Fish Quay, to the south-east of Moville's centre, still operated as a working aid to navigation by the Harbour Board in Derry rather than preserved as a static relic. Seen from the shore, its iron silhouette against the water of the lough gives the Moville seafront a distinctive edge, a working reminder of how much shipping once passed this stretch of coast on its way out to the Atlantic.