Glenfinnan Viaduct is a railway viaduct on the West Highland Line in Glenfinnan, Lochaber, Highland, Scotland. It was built between July 1897 and October 1898 at the cost of £18,904. 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.
Glenfinnan Viaduct forms part of the Mallaig extension of the West Highland Railway which was constructed between 1897 and 1901.
Built entirely of concrete, the viaduct consists of 21 arches, each spanning 15m and has a maximum height of 30m offering spectacular views down Lochaber’s Loch Shiel.
According to myth, during construction a cart-horse and driver were killed when they fell into one of the piers while dumping their load, and were buried in the concrete. Recent research has shown that the incident happened at Loch Nan Uamh Viaduct, further down the line, near Arisaig, and the driver survived. Memorial plaques are at the latter viaduct and at Glenfinnan Station Museum.
Railway services 
The West Highland Line connects Fort William and Mallaig, and was a crucial vein for the local fishing industry and the highlands economy in general, which suffered enormously after the Highland Clearances of the 1800s.
The line is used by passenger trains operated by ScotRail between Glasgow Queen Street and Mallaig, usually diesel multiple units. Additionally in the summer the heritage Jacobite steam train operates along the line. It is a popular tourist event in the area, and the viaduct is one of the major attractions of the line.
- In popular culture
Glenfinnan Viaduct has been used as a location in several films and television series, including Ring of Bright Water, Charlotte Gray, Monarch of the Glen, Stone of Destiny, and three films of the Harry Potter film series.
- Scottish banknotes
The Glenfinnan Viaduct features on some Scottish banknotes. The 2007 series of notes issued by the Bank of Scotland depicts different bridges in Scotland as examples of Scottish engineering, and the £10 note features the Glenfinnan Viaduct.
- Sir Robert McAlpine Project Archive
- "Confirming a West Highland Railway viaduct legend" by Professor Roland Paxton MBE
- "Fort William to Mallaig," in "Great Railway Journeys of the World" by Max Wade-Matthews
- "Current Banknotes : Bank of Scotland". The Committee of Scottish Clearing Bankers. Retrieved 2008-10-29.
Media related to Glenfinnan Viaduct at Wikimedia Commons