Even more holes than Blackburn, Lancashire. At 1m diameter and 75cm deep, so ~0.59m^3, I calculate that to fill the Albert Hall, which a search suggests "has b

Even more holes than Blackburn, Lancashire. At 1m diameter and 75cm deep, so ~0.59m^3, I calculate that to fill the Albert Hall, which a search suggests "has been estimated at" ~100,000m^3 (feels low to me, but it's quoted in many places), it takes around 170,000 of these Peruvian holes.