The Mirny diamond mine in Russia is the world’s biggest hole – it’s 525 metres deep and 1.25km wide.
Mir Mine (Russian: Кимберлитовая алмазная трубка «Мир» Kimberlitovaya Almaznaya Trubka “Mir”; English: kimberlite diamond pipe “World” or “Peace”) also called Mirny Mine is a former open pit diamond mine, now inactive, located in Mirny, Eastern Siberia, Russia.
The airspace above the mine is closed for helicopters because of incidents in which they were sucked in by the downward air flow.