Further rock and debris have fallen beneath Cathedral Cove's picturesque Arch following the extreme weather events over the past year including Cyclone Gabrielle.
The Department of Conservation (DoC) earlier discouraged access in March and August, as parts of the area were either destroyed or significantly damaged.
Rocks described as "the size of large chilly bins" have crumbled from the arch with the slip believed to have occurred on Monday, August 28.
DoC Coromandel operations manager Nick Kelly is asking the public to prioritise their safety.
"We're really concerned people are not heeding the warnings," he said.
"We've consistently said the tracks are closed and there is a danger of rockfall at the beach which could lead to injury."
Kelly said members of the public must not use the tracks, stand or walk under the arch.
DoC staff are finalising semi-permanent signage that warns of rockfall risk, and commercial operators are working to ensure robust health and safety plans are in place.
With the long-term issue of rockfall, a project team will be reimagining the local and visitor experience in collaboration with stakeholders and the public.
"We need to find resilient solutions to the long-term challenges at this site," Kelly said.
He stressed people should take care if they consider visiting.
"People planning to go to Cathedral Cove should properly inform themselves of the risk, and if they're uncomfortable with the risk, they should seriously consider not visiting."
Boats can resume landing in the coming weeks, from the adjacent Te Whanganui a Hei Marine Reserve.
