Pin about the city of Sibay. Sibay is a town in the Republic of Bashkortostan, Russia, located on the border between Europe and Asia, on the east slope of the Southern Urals. Sibay was granted urban-type settlement status in 1938. In 1955, it was granted town status. Sibay is well-known for possessing the deepest open-cast mine in Russia: its colossal Copper-Zinc quarry is almost 2-kilometer (1.2 mi) wide and 500-meter (1,600 ft) deep.