Children under the age of 18 visiting Bosworth Water Park will not be allowed in without a parent or legal guardian accompanying them.
The local beauty spot has made the decision due to people not adhering to social distancing rules.
It came into force on Saturday at 9am.
A statement on the park's Facebook said: "Due to the number of unaccompanied persons under the age of 18 entering our park and failing to abide by social distancing regulations, coupled with the sheer volume of litter and anti-social behaviour caused by a minority of these visitors we have made the following decision.
"From 9am Saturday morning (8th August) we will not admit any person under the age of 18 without a parent or legal guardian that will accompany them at all times.
"Any person under the age of 18 found to be on our premises and not accompanied will be removed.
"Parents please do not allow your children to visit on their own they will be removed.
"We are sorry to have to make this decision but unfortunately a minority of individuals have spoilt this for all."
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