Calvine Double Bridge

Looking across the road bridge

Calvine Double Bridge is a highly unusual, and ingenious, solution to a problem created by the Duke of Atholl when the Highland Main line was constructed through his estates in the 1860s. He stipulated that the railway should cross the River Garry at the same point as the road, so the engineer, Joseph Mitchell, did just that. The two routes cross each other at a skew; the road crossing the river roughly at right angles. The railway crosses on a viaduct, the central arch of three being the widest to cross the road and river in one leap. In 1899 the tracks were doubled here, and a metal girder span built on the north side of the older viaduct, also spanning the road and river in one go.

Records suggest that the original road bridge here dates back to 1765, but it is unclear how much of that structure survives. When Mitchell carried the railway overhead, changes were made to the road bridge below in order to accommodate the new railway line above. The stonework of the current road bridge is fairly regular coursed work, similar to but not the same as that on the viaduct above, however, a bridge built in the 1760s is more likely to have been built with un-coursed rubble, except of course that this is the Duke of Atholl's estate. Further changes were made when the second viaduct was added, with the piers for the new span built into the parapets of the old road bridge.

The bridge is a single stone arch across the river, carrying the single track B847 between substantial stone parapets. The arch is flanked by a pair of substantial buttresses either side of the river on the upstream side, and is now built into the north east pier of the railway viaduct on the downstream side. Due to the railway above, there is a low height limit on the road bridge, as it passes diagonally under the centre of the skewed arch.