The Blue Lagoon near Buxton, a flooded quarry - has inviting turquoise waters, but it is so polluted it's almost as toxic as bleach.
There are warning signs saying it can cause skin and eye irritations and stomach problems, but families and young swimmers are ignoring them.
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A windy day with some possible rain.
It will be a cloudy day but remaining dry.
27-year-old Akim Nicholson has been arrested by police following a five-hour rooftop standoff during which officers were pelted with tiles.