Sex toys and drug paraphernalia were among the 'disturbing' items picked up by a young nature group from a bird hide.
Buzz Bee Nature Group visited the hide at Breydon Water, on the edge of Great Yarmouth, to look for birdlife across the estuary.
But Robert Ashton, group founder, said the group were 'disturbed' to find swathes of litter inside and outside the hide.
"This was clearly human litter abuse, of using the bird hide for a 'hang out' place rather than for bird watching," Mr Ashton said.
"This prompted the children to take measures for a litter pick at the Breydon site rather than a beach, as this is more of an 'our problem' rather than a world problem washing up on our beaches."
But there was more than just crisp packets and empty drinks containers at the site, Mr Ashton added.
"Both children and adults that took part weren't prepared for some of the findings on the litter pick. Alongside the usual plastic bottles and wrappers were sex toys and drug syringe needles.
"We had to take major cautions with what the children were picking up, but the group did a fantastic job of clearing it," he said.
"We hope this little bit of work and effort put in will just highlight the need to dispose of our litter responsibly."
Breydon is a stronghold for birdlife in Norfolk - with Great Yarmouth Wildfowling and Conservation Association being responsible for hide's management.
Michael Pearson, president of the group, offered his "sincere appreciation" to the children for clearing up the site.
He said: "As soon as I heard about the mess I went along and had a look. There was absolutely no rubbish left which shows that the group did a really thorough job. But it also means that we can't be held responsible for something we didn't know about.
"Vandalism is a big issue there, and as far as I'm concerned, it should be up to the police to keep an eye on the place.
"We check it as much as we can, but we can only do so much in keeping away kids on their bikes who use the facilities inappropriately.
"We did put a lock on the hide door at one point but this was just broken into. We don't have cameras either because we're on a tight budget.
"As soon as the summer comes, we will paint the place up and repair any problems so that people can continue to enjoy using the hide."
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