Stuart Thompson, from the RNLI, says one of the risks of tombstoning is the sheer unpredictability of the environment.
"The problem is that you know heights of tides change, conditions change" he says.
"The conditions of the seabed change as well so it's actually quite a dangerous practice".
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Western areas will see the wet and windy stuff continue overnight! And then tomorrow - i'm very sorry to say - there is more of it to come!
Dolaucothi Gold Mines is among five locations battling it out to be crowned Wales' best place in this year's Special Places competition.
It's the latest in a series of incidents, despite safety measures being put in place after the death of an off-duty police officer in March.