In Cooleeny townland alone, field survey identified 44 toghers, the Irish term for a causeway or trackway laid across boggy ground, making this one of the more concentrated clusters of such structures recorded anywhere in the country. That so many were built across a single stretch of wetland says something quietly extraordinary about how much traffic, and how much effort, this landscape once demanded of the people who lived around it.

A survey carried out by Gowen in 1999 recorded the full extent of the Cooleeny toghers and examined their construction in some detail. Most were built from a combination of brushwood and roundwood timbers laid across the soft ground, though six relied on roundwood alone, eight used only brushwood, and one unusually incorporated gravel alongside brushwood. Two of the toghers have been radiocarbon dated, both falling within the Iron Age: one to 388 to 207 BC and another to 372 to 192 BC. These dates place the trackways within a period of considerable activity across Irish bogland landscapes, when communities regularly engineered routes through otherwise impassable terrain, sometimes for practical movement and sometimes, scholars suggest, for purposes that went beyond the purely functional. Wood species were identified in seventeen of the toghers, and the variety is striking: alder, ash, birch, blackthorn, hazel, mountain ash, and willow were all used, suggesting that builders drew on whatever timber was locally available rather than following a single prescribed method. That diversity of material, woven together across dozens of separate structures, gives a sense of accumulated, repeated effort spanning what may have been generations.