Mercury was discovered in Idrija (known as Idria under Austrian rule) in the late 15th century (various sources cite 1490, 1492, and 1497). Mining operations were taken over by the government in 1580. The mineral idrialite, discovered here in 1832, is named after the town.
According to legend, a bucket maker working in a local spring spotted a small amount of liquid mercury over 500 years ago. Idrija is one of the few places in the world where mercury occurs in both its elemental liquid state and as cinnabar (mercury sulfide) ore. The subterranean shaft mine entrance known as Anthony's Shaft (Antonijev rov) is used today for tours of the upper levels, complete with life-sized depictions of workers over the ages. The lower levels, which extend to almost 400 meters below the surface and are no longer being actively mined, are currently being cleaned up.