One, Two, Three of 'Em
Steven Siegel 1997
Not to be confused with Steven Seagal, star of many a questionable martial arts movie, Steven Siegel is an American artist who was born in 1953 in White Plains, just twenty-odd miles north of New York City. His work in Grizedale consisted of only one sculpture, though it came in three parts - a trio of mysterious wooden structures each with a different shape, but all with a thatched roof. It sits on the forest road which skirts the western flank of Bogle Crag and provides a handy shortcut if you're wanting to traverse that side of the forest in a hurry.
I'm not sure if the jauntily-titled 'One, Two Three of 'Em' is still there, or what state it's in. Last time I passed, one of the buildings (the conical one) was starting to seriously lean to one side, and trees had grown up around them, stopping me from getting close.