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Glenfinnan Viaduct

Best known viaduct on the West Highland line, an early example of the use of mass concrete, and starred in four Harry Potter films.

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Near Glenfinnan, Inverness, PH37 4LT

PH37 4LT
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About Glenfinnan Viaduct

The West Highland Railway opened in 1901 between Fort William and Mallaig. The contractor was Robert McAlpine & Sons. McAlpine was enthusiastic about the use of concrete and the Mallaig line was accordingly a proving ground for the use of the new material, mass concrete (not containing steel reinforcement).

Glenfinnan is the most famous of the viaducts on the line, notable for its 21 arches and for being built on a 12 chain radius curve. Another bridge on the line, Borrodale, was for a time the longest single concrete span in the world. Both continue in use.

Located at the top of Loch Shiel in the West Highlands of Scotland, the viaduct overlooks the Glenfinnan Monument and the waters of Loch Shiel.


The viaduct was constructed by Robert McAlpine & Sons which was headed by Robert McAlpine, nicknamed "Concrete Bob" for his innovative use of mass concrete. Concrete was used due to the difficulty of working the hard schist in the area. McAlpine's son Robert, then aged 28, took charge of construction, with his younger son Malcolm appointed as assistant.

Construction of the extension from Fort William to Mallaig began in January 1897, and the line opened on 1 April 1901. The Glenfinnan Viaduct, however, was complete enough by October 1898 to be used to transport materials across the valley. It was built at a cost of GB£18,904.


The viaduct's spectacular location and visual appeal gave it a role in four Harry Potter films. It is now popularly known as the "Harry Potter Bridge" over which Hogwarts Express (The Jacobite Steam Train) passes. In the flying car scene in Harry Potter and the Chamber of Secrets, Ron and Harry in the flying Ford Anglia find themselves being chased across the bridge by the train.



By road: Close to Glenfinnan Station which has a Railway Museum.


The Transport Trust are grateful the Glenfinnan Station Museum who have kindly agreed to host the Red Wheel Heritage Plaque so that it may be seen by all the visitors to the museum and those who pause there on the Jacobite Express trains that run through the summer.

Biddle, Gordon, Britain's Historic Railway Buildings, Oxford University Press, ISBN-10: 0198662475 (2003)

Biddle, Gordon & Nock, O.S., The Railway Heritage of Britain : 150 years of railway architecture and engineering, Studio Editions, ISBN-10: 1851705953 (1990)

Li, Martin. "Introduction: Scotland on Film", Adventure Guide to Scotland. Hunter Publishing, 52. ISBN 1588434060

Thomas,J. The West Highland Railway (1970)

Smith, M. British Railway Bridges and Viaducts. Ian Allan. ISBN 0 7110 2273 9 (1994)

Wade-Matthews, Max. "Fort William to Mallaig," in "Great Railway Journeys of the World"

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