People are being warned against swimming in a former quarry full of chemicals.
It's known as the 'Blue Lagoon' and it's tranquil turquoise waters draw people from far and wide.
But experts say it's PH levels make it almost as toxic as bleach.
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Cold with icy stretches to start Tuesday. There will be sunny intervals and further wintry showers, but snow will become confined to hills
Cold, windy and wintry weather continues until midweek. Cloudier yet milder weather for Thursday and Friday
Cold & windy. Some nice March sunshine developing for the afternnon but further wintry showers, especially later towards evening/overnight