Fifty years ago though, everyone knew it.

Tourists stopped to look as they passed, and locals swelled with pride.

Like the earlier and beautiful King's Bridge at Launceston Gorge, the Longford rail bridge was built by Charles De Bergue & Co of Manchester, to the design of William Doyne.

Both bridges were prefabricated in England, then dismantled and shipped to Launceston to be installed by the local contractor.

The Longford rail bridge arrived in January 1870.

It was largely complete by April 1870, at a final cost of (reportedly) £36,000, awaiting only the four, 4-ton iron pillars to decorate each end.

It was stress tested by Doyne on April 9, 1870, by running a 34-ton locomotive, pulling 11, four-ton wagons of gravel over it and measuring the deflection and vibration.

The bridge is a through-lattice truss, continuous over two 64-metre spans.

These spans exactly matched in length those of the Barwon iron bridge at Geelong, built in 1859.

They were the longest spans in Australia until surpassed by the Fitzroy River suspension bridge at Rockhampton in 1880.

In the huge flood of September 1870, the newly-completed bridge provided the only access to Longford.

William Doyne, who designed four bridges over and along the South Esk, was a pioneer in railway and bridge engineering and construction, and respected throughout Europe and Asia.

Doyne first came to Tasmania in 1861 to do the initial surveys for the Launceston and Western Railway, and designed and oversaw the construction of King's Bridge.

He reflected the 19th century philosophy that major projects should be aesthetically pleasing, as well as functional.

Integral to his iron bridge design at Longford were magnificent cast-iron pillars at each end.

The bridge was greatly admired for a century afterwards.

Around 1967 the famous pillars at each end were removed as construction of the Poatina hydro station required huge turbines to be transported by rail, and there was insufficient clearance at the bridge.

They were heavy and damaged, so instead of being replaced, the pillars were scrapped.

Sadly, this destroyed the aesthetic design of the structure and its fascination for visitors.

It was a great loss to the community and to the built heritage of Tasmania.

Fortunately there is now a move afoot in Longford to restore this magnificent bridge to its original design by recreating and replacing the great pillars, using lightweight modern composite materials.

This will restore the historic integrity and enhance the beauty of the river and surrounds.

It is a project that will hopefully engage the community and be realised.

Restoration of the bridge to its original concept would provide a feature of great interest to visitors and a focus for celebrating 150 years of railways in Tasmania in 2021