Looking at photos like these scares and fascinates me in equal doses. The sheer scale of these holes reminds you of just how tiny you are. Mirny Diamond Mine, Siberia. I'm pretty sure most people have seen this one. It's an absolute beast and holds the title of largest open diamond mine in the world, at 525 metres deep with a top diameter of 1200 metres there's even a no-fly zone above the hole due to a few helicopters being sucked in.
Glory Hole - Monticello Dam - A glory hole is used when a dam is at full capacity and water needs to be drained from the resevoir.This is the glory hole belonging to monticello dam in california and it's the largest in the world, its size enabling it to consume 14400 cubic feet of water every second.
