This stunning lake at Harpur Hill in the East Midlands of England is just begging you to dive in, no? Problem is, the quarry pool, known as the Blue Lagoon, has a pH level comparable to bleach and is teeming with garbage and dead animals. The bright blue hue (and the high pH) comes from the quarry stone. Signs warning visitors not to take a dip didn't work, so now the High Peak Borough Council recently dyed the water black. "It's not pretty any more," local business owner Rachel Thomas told the BBC. "They don't think they're on holiday in the Bahamas any more, they know they're in Harpur Hill."