It’s a little tricky to get to the fascinating Corlea Trackway Visitor Centre, which is actually across the county border in Longford and signposted along a minor road off the R392, 20km northeast of Athlone, but its isolation in the midst of a desolate bog only adds to the appeal of the place. In 1984, Bord na Móna (the Peat Board) discovered a buried togher, an early Iron Age trackway, while milling turf here in Corlea raised bog. Dated to 148 BC, the trackway was made of split oak planks up to 4m in length that were meant to float on the bog surface, one of the most substantial and sophisticated of many such prehistoric roads found in Europe. However, the builders knew more about woodworking than the properties of the bog, because within ten years the heavy planks had sunk into the peat – which preserved them perfectly for the next two thousand years. The road connected dry land to the east with an island in the bog to the west, but it’s clear that such a prestigious construction was intended for more than just the movement of animals by farmers: it may have been part of a ceremonial highway from the Hill of Uisneach, the ritual “centre of Ireland” that marked the division of the five ancient provinces, between Mullingar and Athlone, to the royal site of Rathcroghan in Roscommon, via the narrow crossing of the Shannon at Lanesborough.