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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England scored an extraordinary six goals against Panama in today's World Cup match.
Fine, dry and sunny this afternoon. Light winds, and feeling very warm.
After a cool start in rural areas, this afternoon will be dry and sunny.