A SCENIC Scottish railway line has reopened after nine days of works.

The West Highland Line, connecting Glasgow to Oban and Fort William, closed on March 16 for an upgrade of the historic Rannoch Viaduct.

The bridge helps connect Loch Linnhe and Ben Nevis with the central belt, traversing the picturesque Rannoch Moor.

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During the works, Network Rail contractors replaced 50 life-expired softwood timber sleepers that support the tracks over the 208 metre bridge.

They also replaced rails throughout the structure, and renewed several areas of track in the vicinity of the bridge.

Away from the viaduct, engineers modernised the signalling system on the approach to Fort William station, about 35 miles up the line.

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This saw some signalling posts moved, and the lights converted to LEDs.

Zoe Monkhouse, Network Rail’s project manager for the project, said: “Our team has worked around-the-clock to deliver this project safely and efficiently and to get the line re-opened for passengers as planned.

“This investment will extend the lifespan of the structure, improving the long-term reliability of the line, and we are pleased to have completed the work on time.

“We would like to thank passengers for their patience during the project.”

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The viaduct was built in 1894 to cross a bog between Rannoch and Corrour, the highest-elevation railway system in the UK.

Railway planners thought constructing the viaduct would be simpler than filling in the bog.

The Rannoch Moor – chronicled by Robert Louis Stevenson in his novel Kidnapped – was difficult for the engineers of the time to construct a railway line over due to the boggy terrain.

The line has been described as "best in the world" by Robin McKelvie, a travel writer contributing to The National.

In a story for the paper last year, McKelvie lauded the views passengers get from trains travelling on it, saying it beat those on any other railway line he's ridden on.

The line also plays host to the Glenfinnan Viaduct, immortalised by the Harry Potter films.