The canal runs some 60 miles (97 km) from northeast to southwest. Only one third of the entire length is man-made, the rest being formed by Loch Dochfour, Loch Ness, Loch Oich, and Loch Lochy.[These lochs are located in the Great Glen, on a geological fault in the Earth's crust. There are 29 locks (including eight at Neptune's Staircase, Banavie), four aqueducts and 10 bridges in the course of the canal.
https://en.wikipedia.org/wiki/Caledonian_Canal