A huge crack running for 100m (328ft) has opened up along a section of the Jurassic Coast in Dorset.
It was said to be over a metre deep on April 12th and appeared between Bowleaze Cove and Redcliff Point at Preston near Weymouth.
People have been urged to stay away from the popular clifftop beauty spot a as the soil is very unstable.
This area is well-known for landslips due to its geology of permeable limestone over impermeable clay. The movement has been going on for several years but this latest slip has happened quickly.
Thousands of tonnes of earth have given way and will continue to slip away, changing the landscape of the renowned coastline.
It is unknown when the cliff will fall down on the beach, but walkers and tourists are now being warned to steer clear of the chasm.
This gigantic landslip was caused by heavy rainfall in the last few months.
Fossil hunters and beachgoers are also being warned as the crack will mean extra clay and mud on the shore below the cliff.
As if an earthquake had struck.
The thing is that this geological process is all part of a progressive evolution of the coastline.
If hundreds of thousands of tonnes of rock have moved there is an increased risk of rock falls and mud that will spill out onto the beach and create a danger.
Coastguards said the crack started to appear at the end of March.