Coroner Sheriff Payne told the hearing that Miss Blackman's death could not have been predicted.
He said the National Trust, which owns a stretch of the beach where the tragedy happened, appeared to be doing all it could to warn visitors of the dangers presented by the 100ft cliffs.
"Sadly, Charlotte Blackman died as a result of an accident. It was a sudden act of nature that nobody could have predicted at that time."
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Dry with some winter sunshine, but feeling cold.
Health bosses across the West Midlands are urging people to make the right choices about health care.
A dry day ahead with good spells of sunshine, but cold and frost continuing.