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."
More top news
Fine and sunny, after a cold start.
Cold start, then dry and sunny.
Laurence Llewelyn-Bowen pledges to fix The Magical Journey Christmas experience he designed, which shut down after a string of complaints.