The slip happened on Sunday afternoon, July 12, on the stretch of beach beneath the cliff path linking the pier and the Barrage. Eyewitnesses posting on social media said the cliff gave way at around 4.30pm, sending a cloud of dust and rubble onto the rocks below while the area was busy with people enjoying the hot weather.
Some described hearing stones “constantly” trickling down from the cliff face in the moments before the main fall, while others said they felt “lucky” no one had been hurt.
A spokesperson for the Vale of Glamorgan Council said the authority was aware of a “landslip on the coastal section between Penarth Pier and the Cardiff Bay Barrage”.
They said this stretch of coastline had a “well-documented history of cliff instability, landslides and rockfalls, particularly following prolonged weather events and coastal erosion”.
Council teams were on Monday assessing the extent of the collapse and would “take any necessary action to ensure public safety”, the spokesperson added.
The public has been strongly advised to stay away from the affected area and, as a precaution, keep clear of all cliff faces and the areas directly beneath them because landslides and rockfalls “can occur without warning”.
Residents and visitors have been urged to follow all warning signs, barriers and safety notices when using coastal paths and beaches around Penarth.
The council said it would continue to monitor the cliffs and share further updates as they become available.
Several local people commenting online said they were not surprised by the latest fall, describing the cliffs as “always unsafe” and warning others never to sit directly underneath them.
Others pointed to recent rockfalls at nearby Jackson’s Bay and Penarth Marina and called for extra signage or engineering work to protect beachgoers along the Vale coastline.
The council has reminded anyone heading to the seaside to check tide times, keep a safe distance from cliff bases and edges, and to call emergency services if they witness a significant rockfall or see someone in immediate danger.
