Hundreds of bottles and cans of alcohol have been confiscated by police to stop drinkers using a North Yorkshire beauty spot "like an Ibiza nightclub".
Crowds of revellers on the UK's hottest-ever day flocked to Richmond Falls where officers seized several big sound systems and large canisters of nitrous oxide, known as laughing gas, which are sometimes used to get high.
They also took away 200 bottles of beer, cider, vodka and other spirits on Tuesday.
Some local residents were concerned about antisocial behaviour linked to hot weather, according to North Yorkshire Police.
The force said they dispersed five men from Middlesbrough because they were behaving antisocially and arrested a youth from County Durham on suspicion of assault following a disturbance.
Inspector Martin Metcalfe said: "Residents quite rightly don't want their town to be used like an Ibiza nightclub and we're doing something about it.
"As temperatures soared well into the 30s yesterday and hundreds congregated at Richmond Falls, my team and I took action to prevent crime and antisocial behaviour as well as all the litter and mess this leaves behind."
He added: "We simply will not tolerate antisocial behaviour, which is often committed by large groups who travel in from other areas and behave with no respect for the community they're visiting. And yesterday we used public space legislation to tackle it."
Eighteen traffic offence reports were issued to those travelling to and from the area, including for not wearing a seatbelt and for causing an obstruction when parked.
Seven barbecues were also put out because of the dry and dangerous conditions.
Police said the owners of the sound systems were able to get them back from a police station at the end of the day and "were given words of advice about using them in public places".