Forty-four of them have been identified in Cooleeny townland alone, each one a togher, the Irish term for a timber trackway laid across boggy or waterlogged ground to make it passable. They are invisible from above, preserved by the airless, acidic conditions of the bog that have kept their wood intact for more than two thousand years.

A field survey carried out in 1999 recorded these toghers in detail, revealing considerable variety in how they were built. Most combine brushwood, the thin, flexible stems of shrubs and young trees, with roundwood, meaning larger, shaped timber poles or lengths. Six were built from roundwood alone, eight from brushwood only, and one unusual example incorporated brushwood and gravel together. The range of wood species identified across seventeen of the toghers reflects a pragmatic use of whatever grew nearby: alder, ash, birch, blackthorn, hazel, mountain ash, and willow all appear. Two of the toghers have been dated by radiocarbon analysis to the Iron Age, one to 388 to 207 BC and another to 372 to 192 BC, placing their construction during a period when the Irish landscape was being actively managed and traversed, and when crossing a bog on foot would have been a genuine logistical problem requiring an engineered solution. The fact that so many separate trackways exist in a single townland suggests repeated, deliberate effort over time rather than a single episode of construction.