Police broke up a rave that had attracted up to 120 young people to a quiet Chorley beauty spot.
The would-be revellers descended on picturesque Rivington to party into the night.
Police said they questioned a group of organisers of the event and seized sound equipment.
Sergeant Kevin Mountain, of the Chorley Neighbourhood Policing Team, said: “A rave was being set up at Rivington.
“We got wind there was information about the village a rave was being planned.
“Some neighbourhood officers went up just before about 10pm.
“There were large numbers of young people gathering in the area, about 120.
“A party was located near to Liverpool Castle where some sound equipment was set up and in the early stages of people arriving.
“Four organisers of the event were identified by officers.
“The sound equipment has been seized by police and further inquiries are ongoing in relation to a possible offence of an unlicensed music event.”
He added: “There were no arrests and the majority of people disappeared without incident.
“No doubt, this action prevented this party becoming established. In the past we’ve had noise from this type of event.”
The incident happened on Friday, October 4.
The location for the rave was the ruins of Rivington Castle, a folly which was built by William Lever as a scale replica of Liverpool Castle at Coblowe Hillock near the Lower Rivington Reservoir. The land is owned by United Utilities
In 2009, more than 40 police officers stopped a massive rave at the same spot which had attracted over 400 young people.
Residents living more than half a mile away had complained abut the loud music.
Three people were arrested.
A spokesman for United Utilities said: “These incidents have been a pain for us in the past, causing damage to our property and land. Bollards and gates have been knocked down and we’ve had to carry out big clean-ups afterwards.
“Also, there are no toilet facilities in the area and water from this land drains into our reservoirs, supplying people’s drinking water.”
Police say they have now increased patrols in the area and are working with the United Utilities in an effort to prevent any further illegal gatherings.