The Caledonian Canal was constructed in the early nineteenth century by Thomas Telford through the Great Glen, on a geological fault in the Earth's crust. It connects the Scottish east coast at Inverness with the west coast at Corpach near Fort William. It runs some 60 miles (100 kilometres) from northeast to southwest and reaches 106 feet (32 metres) above sea level. Only one third of the entire length is man-made, the rest being formed by Loch Dochfour, Loch Ness, Loch Oich, and Loch Lochy. There are 29 locks (including eight at Neptune's Staircase, Banavie), four aqueducts and 10 bridges.