PENARTH beach is now safe to use after “natural weathering” caused a 150 tonne landslide of rock and mud over the weekend.
Council officials warned that while there may be minor rock falls the beach is now safe to visitors who show “common sense” and walk a safe distance away from the cliff base.
Coastguards said it was a lucky nobody in the incident.
Visitor Angela Gwyn, who was walking along the beach with her husband and two grandchildren, recorded the dramatic footage on her mobile phone.
It was thanks to her footage that the fire service didn't spend hours clearing through the rocks as they could confirm nobody was trapped by the landslide.
Mrs Gwyn said that the cliff landslide “sounded like an earthquake” and she grabbed her grandchildren and ran when larger chunks of rock started to fall.
Vale Council officers spent two days inspecting the landslide and have now put up safety tape either side of the section of the beach affected.
Miles Punter, director for visible services at the Vale Council, said it was likely that the landslide was caused by natural weathering of the cliff.
“The council undertakes annual inspections of all cliffs along the Vale’s coastline to assess any potential safety issues,” he said.
“Evidence gathered during previous inspections, as well as during our most recent site visits, suggests that this latest fall was caused by natural weathering of the cliff. There have been many falls of this nature and size along this section of coastline in the recent years.”
He added that the land at the top of the cliff was privately owned and the council had offered advice to the land owner about how the effects of natural weathering could be mitigated in the future.
Shan Bowden and Keri Hutchings, town clerk and deputy town clerk of Penarth Town Council, inspected the landslide on Monday.
Shan Bowden said the Kymin, on top of the cliff, which is owned by the town council, was unaffected by the landslide as it was about 50 to 60m away from it.
She added that as a precaution they had put up a temporary boundary tape at the top of the Kymin to stop people peering over it.
The landslide happened at around 1pm on Sunday, April 13, near where the former multi-storey car park was based, in between Penarth Pier and the Old Custom House.
At the time of the incident hundreds of people were enjoying the sunny weather walking along the Esplanade and near the pier.
Coastguards, ambulance crew, the fire service and police all attended the scene and closed off the section of the cliff that was affected.
Penarth Fire Station green watch manager Colin Pritchard said that people should always stay a safe distance away from the cliff edge and that there were always bits of rock falling down.
Penarth Coastguard station officer Paul Gallone said it was a "lucky escape" that nobody was trapped by the landslide when the beach was so busy.
"Luckily someone saw it happen and could confirm there was nobody underneath it," he said.
"If not it could have been a different story and it would have been a rescue operation.”
He added that it wasn't unusual for cliff landslides in Penarth, but said that they usually happen nearer Lavernock Point.
South Wales Fire Service group manager Graeme Smith said it was one of the biggest landslides he had seen for a while.
He added that the woman that witnessed it was a "life saver" in terms of preventing the emergency services from spending hours going through the rocks.
Penarth and Cardiff South MP Stephen Doughty said that the landslide was a “stark reminder” of the dangers of living near the coast and that the issue of coastal defences and erosion should be taken seriously.