Lifeboat crews have been forced to rescue people from the "extremely dangerous" Birnbeck Pier four times in the last fortnight.
Weston RNLI were called after three people were cut off by the tide on Weston-super-Mare's Birnbeck Island at 6.40pm on Wednesday (April 29).
Weston Seafront rangers and police also attended the incident, the fourth emergency response in 10 days at the derelict pier, amid the coronavirus lockdown.
A chunk of Birnbeck Pier, built between 1862 and 1867, came away after Storm Ciara in February.
In a Facebook statement, Weston Seafront warned: "Trying to cross the pier is extremely dangerous due to its condition, also trying to cross using the gravel causeway is highly dangerous due to fast moving tides and should never be attempted.
"As well as putting yourselves at huge risk you are also putting the lives of our emergency services at risk."
An RNLI spokesman added: "Our crew is currently separated into two teams to minimise contact so we can continue to provide our lifesaving service.
"Operating in the current conditions places a heightened risk to the volunteer crew and their families so we are asking anyone considering crossing to Birnbeck to stay away."
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The RNLI has said people can enjoy a walk or cycle along the seafront to exercise, but told them not to visit Birnbeck "at any time".
"Please respect the latest government advice, stay home, protect the NHS, save lives," the spokesman added.
