What makes the site quietly remarkable is the continuity: each bridge built here was almost certainly placed on or very close to its predecessor, meaning the present nineteenth-century stone span sits above centuries of accumulated effort to cross one of Ireland's most significant rivers.

The earliest documented bridges at this location were built by Toirrdelbach Ua Conchobhair, King of Connacht, in 1140 and again in 1154. The annals refer to them using the term 'cliathdroichet', which translates roughly as wicker-bridge, suggesting a timber and wattle construction rather than anything in stone. These were almost certainly positioned at or near existing fording points, places where the river was already known to be passable. After the upheavals of the intervening centuries, an Act of Parliament was passed in 1663 for the construction of a new bridge at what was then called Ballilegue, spanning the Shannon between counties Longford and Roscommon. Sir George Lane completed that bridge in 1667, and it drew considerable admiration: a 1682 account described it as 'a fair stone bridge built by the Contribution of several of the Adjacent Counties', going on to claim it was at that time 'the largest in the Kingdome' in both length and breadth. The present bridge, built somewhere between 1835 and 1843, was almost certainly constructed on the footprint of Lane's seventeenth-century structure, which had itself replaced the medieval bridges before it.