|Location Map ( geo)|
The A9 crosses the River Carron at South Broomage, just south of Larbert on a modern concrete bridge, however there seem to have been a lengthy sequence of bridges around here.
The New Bridge
The new bridge carrying the A9 is built on a skew to remove the sharp bends of the old bridge, and as such is a concrete lattice arch structure as was often used with skew bridges. Carrying a wide S2 carriageway with pavements on both sides, the bridge was built as part of an upgrade to the A9 through Larbert, including a new line into the town centre, avoiding the narrow Falkirk Road.
The Old Bridge
One of the modern bridges predecessors is still standing just a little upstream from the current A9 bridge, and indeed is still open. Crossing the river at right angles rather than the skew of the modern bridge, the old bridge allows traffic from the A9 to turn right into Lochlands Loan without a sharp double-back, it is one way.
The bridge itself consists of two identical stone arches across the river and dates to the early 19th Century, although no more accurate date is available. Other than a recessed ashlar arch ring, the bridge is just plain rubble, with the western arch spanning the main river channel and the eastern arch little more than a flood arch.
The Roman Bridge
Back in 1777 the River Carron was being deepened to improve it as a shipping channel, and reports from the time suggest the discovery of the remains of a Roman Bridge in the vicinity of Larbert. Unfortunately, there was little precision in this report, and no supporting evidence has ever been found since. The most likely site is now believed to have been a few hundred metres further upstream where a weir was constructed.
The existince of a Roman Bridge in the area is not as daft as it may sound, with a series of Marching Camps and Forts having been discovered to the south of the River Carron, and the Antonine Wall is only about a mile away. Indeed, a crossing of the Carron near here is highly likely, although whether it would have been stone as reported or just wood is less certain.