Sonnagh Fort

A ringfort on the ridge

Seven ringforts ring the village of Aughnacliffe in north County Longford, and Sonnagh is the best preserved of them. It sits on top of a drumlin, a low rounded hill left by the last ice age, with a commanding view east over Lough Gowna. The name says what it once was: Sonnagh comes from the Irish sonnach, ‘palisade’, and a timber wall would have run along the bank when the fort was in use.

This was a home, not a barracks. Ringforts like this were protected farmsteads, and the archaeologists who study them are clear that most were built for status and security rather than warfare. The bank kept livestock in and wolves out; the earthworks announced that someone of standing lived here.

Reading the earthworks

The fort measures 46 m in circumference. An inner bank of earth and stone stands 0.5 to 0.9 m high, then a scarp and a wide fosse (ditch) drop away to an outer bank that rises to 1.9 m, noticeably taller than the inner one. The entrance is a 4 m break in the inner bank on the south-east side, the original way in, positioned so the household could watch who came and went.

Dating a ringfort by eye is impossible, and the honest answer for Sonnagh is a wide one: forts of this type were built across a long span from the Bronze Age through to the late Iron Age, roughly 2500 BC to AD 500. Inside, houses were built of post and wattle, the walls two rows of woven wattle about 20 cm apart, packed with straw and bracken for insulation and roofed with thatch. A spring rises just east of the fort, which is likely why this particular drumlin was chosen: defensible ground, fertile fields, and water on the doorstep.

One thing worth knowing before you picture the OPW as landlord: the site is a National Monument in state care, but the land itself is privately owned. Treat it accordingly and keep to the access track.

Walking the fort today

There are no panels, no fencing and no ticket booth, just the banks, the grass and the sky. Walking the perimeter takes only a few minutes, but the low sun of early morning or late afternoon throws the curves of the earthworks into relief and is easily the best time to see the shape of the place. From the crest the view runs out over Lough Gowna and the patchwork of small fields toward the Westmeath border.

If you want to make more of the trip, the Aughnacliffe Heritage Trail, opened in 2023, is a 4.2 km looped walk for pedestrians and cyclists that links the fort with the nearby dolmen and Mass Bridge. Longford County Council spent €200,000 on it, and it is the easiest way to see the fort as part of the wider landscape rather than a single stop.

Planning your visit

Sonnagh is free and open year-round, reached by a short track from the road. The ground is uneven, the soil near the fosse stays soft, and the banks turn slippery after rain, so wear proper footwear and pick a dry day if you can. There are no facilities on site; the nearest toilets and cafés are in Aughnacliffe or Ballinalee, both a short drive. Dring Car Park, about 3.5 km east near St Joseph’s Church, is a useful larger parking spot if the roadside is tight.

Quick reference

Pair Sonnagh with the Aughnacliffe dolmen on the heritage trail, or with the Norman motte at Granard, and you have a half-day of north Longford history. Come before midday for the light on the banks.