Windmill Hill Cutting is a large cutting on the dual gauge railway east of Toodyay in Western Australia. The cutting was constructed between 1963 and 1964 for the Eastern Railway route through the Avon Valley, and is part of the interstate standard gauge railway connecting Perth with the rest of Australia. About rocks were excavated, making the project a major one.: December 1962 and into early 1963 editions of the Railways Institute magazine had articles about the engineering achievements of the Avon Valley works
The route became operational in February 1966.https://www.railheritagewa.org.au/archive_scans/displayimage.php?pid=19804 Rail heritage WA photo collection has 44 named images of the cutting The lookout point for the cutting has a plaque that claims one of the deepest in Australia, with the depth at and length as .See photo in gallery 'Plaque at lookout' The Avon Valley cuttings had also uncovered sections of unstable rock, and effort was made to fix walls where required.
Due to the size of the cutting, the underlying geology is exposed to give a clear exposure of rock formations. It was nominated as a geological heritage site in the 1990s.
See also Railway cutting
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