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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Scattered wintry showers will continue overnight. Clear spells will allow a frost to develop by morning.
It will stay windy overnight and wintry showers will continue to feed across the region, especially in the north and west.
'Stressful' and 'nerve wracking' is how parents think the process for how secondary school places are awarded - but is there another way?