Something I remembered from visiting Stonehenge a long time ago: the standing stones are impressive things, having been there for about four thousand years or s

Something I remembered from visiting Stonehenge a long time ago: the standing stones are impressive things, having been there for about four thousand years or so if memory serves. But also in the surrounding area are piles of dirt from approximately the same era. I wasn't expecting that. It seems that every non-trivial modern construction project leaves behind a pile of dirt somewhere, usually as an unintentional side-effect rather than an end in itself. And these piles of dirt it seems stick around for a really long time if no one goes out of their way to flatten them back out. I remember once reading about someone, I think he was a bored meteorologist in the wilderness of Alaska with a bulldozer and a lot of time on his hands. The story goes that he used the bulldozer to write something offensive (I don't think the story said what, exactly) and the local legislature chose not to do anything about it because then the offensive message would be part of the official records of the legislature. Maybe it's an urban legend; I wasn't able to find it with a quick google search. But I'd like to think his message will be visible from space long after most modern constructions have been torn down or destroyed by the slow process of time.