Piles of rubbish were left behind on Dartmoor after an illegal rave, sparking an eight-hour clean-up operation.
Empty bottles, drinks cans and a destroyed gazebo were among the piles of waste left behind on the weekend of February 12-13.
It took a group of Dartmoor Rangers eight hours to clean up the mess.
A spokesperson for Dartmoor National Park Authority urged people to contact the police if they hear of similar incidents in the future.
"It’s hugely frustrating, not just for our Rangers but for landowners, farmers, residents and all the people who love Dartmoor," they said.
"It diverts Rangers away from other important things like practical conservation work which protect and enhance Dartmoor.
"We’d continue to encourage anyone who sees or hears incidents like this to contact the police so it can be dealt with swiftly."
The rangers - who provide communication between the National Park Authority, local communities, landowners, partner agencies and visitors - said it took more than eight hours to restore the site to its prior condition.
They said it is time, money and "valuable resources" which "could have been better utilised" in a Facebook post.