Corlea Trackway

In 1984 turf cutting in Corlea bog exposed a road built of massive oak planks laid across birch runners - a togher, or bog trackway, about two kilometres long and wide enough for wheeled vehicles, which is rare. Dendrochronology dated the timbers precisely: the oaks were felled in 148 BC. It is the largest structure of its kind found in Europe from that period, and why it was built for such a short-lived crossing of an impassable bog remains debated, with ceremonial as well as practical explanations proposed. Waterlogged oak decays fast once exposed to air, so an eighteen-metre section was lifted and is now displayed inside a purpose-built hall with humidity control - the only way it could survive. The centre explains the excavation and bog archaeology, and a short boardwalk runs out onto the bog outside where the rest of the trackway remains buried and rewetted.

What to look for

• The preserved section - eighteen metres of oak road, kept in humidified conditions.
• The dating - timbers felled in 148 BC, fixed by tree-ring analysis.
• The bog boardwalk - out over the ground where the rest lies buried.
• The excavation story - how it was found by turf cutters in 1984.

When to go

April to September - the centre is seasonal and closed for much of the year, which catches people out. Tours run at intervals through the day.

Good to know

Seasonal opening only; check before travelling. The visible trackway is one eighteen-metre section indoors - the rest is buried under the bog. Small site, an hour or so.

Nearby

Longford town is north; Clonmacnoise and the Shannon are south-west.

Key facts