The low, hump-backed crossing over the River Awbeg at the north-east end of Buttevant is something else entirely. Its older southern half has been dated with confidence to the thirteenth century, which places it among the earliest surviving road bridges in the country, and scholars of medieval engineering have described it as a landmark in the national context. Traffic still uses it, or did until relatively recently, which means that for much of its existence this structure carried the main road between Cork and Limerick.

The bridge is built in two distinct sections, and the join tells its own story. The earlier, downriver face is 4.55 metres wide and carries four pointed segmental arches, a form common in medieval construction, where the arch rises to a point rather than a full semicircle. The voussoirs, the wedge-shaped stones that make up each arch, are roughly cut limestone, and the spans widen slightly as you move from east to west, from about 2.6 metres to 3.5 metres. One arch near the western end is noticeably higher than the others and incorporates what is known as a drop arch, a slightly more complex form, and the distortion visible on the eastern side was probably caused by movement in the stones when the temporary timber framework used during construction was removed. The piers sit directly on bedrock, their footings now protected by concrete aprons added in more recent times. The upstream side of the bridge was widened by roughly 2.1 metres at a later date; this newer section has more cleanly cut voussoirs and thickly pointed cutwaters, the angled projections on piers designed to divide the current and reduce water pressure. The widening was probably carried out by a turnpike trust, the bodies responsible for maintaining toll roads in eighteenth-century Ireland, sometime between 1730 and 1800. The bridge appears on the Down Survey barony map of 1655 to 1656, and one researcher has proposed that it may originally have sat within a northern extension of Buttevant's medieval town walls.