[1] It was once a busy main route in and out of St Enoch station but that terminus closed in 1966 and was demolished in 1977, and since then the bridge is only used for empty stock movements, as the bridge forms a key link between Glasgow Queen Street and Glasgow Central.
If a project known as Glasgow Crossrail goes ahead then the bridge and associated track will see passenger services once more.
It consisted of twin-lattice parallel iron girders in seven spans; the engineers were John Fowler and J F Blair, and the contractor was Thomas Brassey & co.
In 1898 the bridge was completely rebuilt, and widened for quadruple track; compressed air excavation for 13-foot (4 m) diameter steel piers were used.
There is a decorative cast-iron cornice and parapet, and towers and half turrets in red sandstone.