The structure they form is modest almost to the point of invisibility: less than three metres long, under a metre wide, and only fifteen centimetres deep. Yet that very modesty is what makes it interesting. This is not a monument or a burial or a ritual enclosure. It is a road, or the smallest functional remnant of one, built by someone who simply needed to cross a patch of bog without sinking.

The structure belongs to a category known as a togher, the Irish word for a trackway laid across soft or waterlogged ground. Toghers were typically constructed from timber, brushwood, or peat sods, and they range in sophistication from elaborate planked causeways to the kind of minimal arrangement found at Derryoghil, which is classified as a class 3 togher, meaning it was built from roundwood rather than split or dressed timber. The seven birch roundwoods here were orientated east to west when recorded in 1988, still lying roughly as they were placed. Radiocarbon dating subsequently placed their felling somewhere in the late Bronze Age, a period when Ireland's midland bogs were being crossed and worked by communities who left very little behind except, occasionally, the wooden paths they built to get from one dry place to another.