Hanging Rock, also known as Mount Diogenes, is a distinctive geological formation located in the Macedon Ranges of Victoria, approximately 70 km northwest of Melbourne. Formed around 6 million years ago, this rare volcanic feature, known as a mamelon, rises 105 meters above the surrounding plains and is composed of solidified lava that created unique rock formations and pinnacles.

The area holds cultural significance for the Woi Wurrung (Wurundjeri), Djaara, and Taungurung peoples, who are the Traditional Owners of the land. Hanging Rock gained international fame through Joan Lindsay's novel Picnic at Hanging Rock and its 1975 film adaptation, which added an air of mystery to the site.