A beautiful "Blue Lagoon" located in the East Midlands of England is harboring a dark secret -- it's filthy.
The picturesque quarry pool is littered with trash and dead animals, and boasts a dangerous pH level of 11.3, according to the Telegraph.
"It has similar pH levels to bleach and is extremely cold," a High Peak Borough Council spokeswoman reportedly said. "There are also a number of hazards, there was a car abandoned in there and all sorts of rubbish, but it still looked a lovely turquoise color."
Swimmers flocked to the pool's turquoise waters, despite numerous signs warning of the quarry's dangers.
"It was absolutely beautiful to look at but was horrendously dangerous," local business owner Rachel Thomas told the BBC.
Finally, the local council resorted to dyeing the water black in an effort to deter swimmers, the Telegraph reports.
"It's not pretty anymore," Thomas told the BBC. "They don't think they're on holiday in the Bahamas any more, they know they're in Harpur Hill."