The western, downstream side presents round arches, while the eastern side shows pointed ones, a hybrid of forms that suggests either a long construction process, a change of plan mid-build, or simply the pragmatic hand of a mason working with what the stone allowed.

Built around 1725, the bridge is a narrow, hump-backed structure of coursed rubble limestone, the kind of construction where stones are laid in rough but discernible rows rather than set randomly. The voussoirs, the wedge-shaped stones that form and support each arch, are described as thin and roughly cut, giving the bridge a utilitarian character rather than a refined one. It was built to carry people and goods across the Dalgan River at a point where Mayo meets Galway, and the county boundary still runs through it today. The upstream face features tall cutwaters, projecting piers that divide the current and protect the bridge's foundations from the force of the river. These have since been capped in concrete or render, and a pipe has been threaded through them at some point, a small sign of the bridge being quietly pressed into service beyond its original purpose. More visible interventions include metal tie rods and plates inserted into the northern four arches, along with new pointing and cement copings along the top, repairs that speak to ongoing efforts to keep a three-hundred-year-old structure standing.