Nic Lonsdale, duty watch manager at Portland Coastguard, said: "We are urging people to observe the warning signs and stay away from the edge." The cliffs at Durdle Door and Lulworth have been crumbling since the start of year.
In January, the steps to the famous landmark collapsed. Earlier this month, coastguards warned that the path was beginning to fall away.
More top news
Holly has the latest Bank Holiday weekend weather.
The Duchess of Sussex took a great interest in the design.
Pupils at Castle Primary in Portchester dressed up as superheroes to welcome back Harry St Ledger after treatment for a brain tumour