The peak of Monte Cimino in Central Italy is crowned by an ancient beech forest and massive volcanic rocks. None, however, are as famous as the sasso menicante (trembling stone), which was already known to Pliny the Elder, who recognized it as a natural wonder in his Natural History.

This massive trachytic peperino rock was hurled to its present resting site during the age of Monte Cimino's volcanic activity, between 1.35 million and 800,000 years ago. When the boulder crashed on the mountain, it found itself balanced on another buried volcanic rock. Until a few decades ago, the massive 250-tonne monolith, which measures 8.5 meters (28 feet) in length and 3 meters (10 feet) in height, could swing with the assistance of a lever, usually a log or branch.Nowadays, because of the accumulation of sediment, the boulder stands still. But all of those who visit this unusual natural monument give it a push, just to check.