Not done anything naughty outside since I was a teenager I think, various bits of woodland/parks. Apologies to the canoeists of Tonbridge for what they might have seen one time. I’d be up for it but it’s just not really come up as an option 
Closest I’ve got was a comedy fumble in the interactive mineshaft exhibit (wahey!! no jk my mineshaft went unfilled) at the National Coal Mining Museum when no-one was in the building we were in. Even that was 2015 FFS.