A toxic pool of bright blue water at a former quarry in Derbyshire has been dyed BLACK - to stop swimmers.
Kids have been going for a dip in the 'Blue Lagoon', despite
It got its pretty blue colour from the chemicals in the quarry stone, but they can cause skin irritations and stomach problems.
The water at the Harpur Hill quarry near Buxton also contains rubbish and dead animals.
Local businesswoman Rachel Thomas said the dye was working.
She said: "It's not pretty any more. They don't think they're on holiday in the Bahamas any more, they know they're in Harpur Hill.
"It was absolutely beautiful to look at but was horrendously dangerous."