Some years ago he bought a small mountain in upstate Maine. He's been tinkering around on it since then, developing roads and houses. Each year the effort becomes a bit more eccentric.
This summer he's been focused on a steep bank on the mountain's shoulder. He's cleared about 10 acres, flattened them into a wide mound, and built an immense stone palace facing the road composed of huge boulders found around the property. They're carefully layered into two berms encircling a flat area about one acre in size. At its peak the wall is about 60 feet high and rises in two tiers with a grassy bank between the levels. A staircase of flat rocks runs up the center. It looks like a cross between an Aztec temple and a Roman amphitheater plopped into the Maine woods.
Why is he building this? No one knows. It's not religious. It serves no purpose. Few people have seen it. It's completely original and unconnected to any societal function.
If the Maine temple has any explanation it's that Adrian likes to build with rocks —is compelled to build with them— and he has the time and money to make whatever he feels like. He is completely tuned to his muse, with no outside interference. The closest analogy I can think of is something like Watts Towers or Coral Castle or maybe Richard Dreyfuss building Devil's Tower models in Close Encounters.
I think the lesson for photographers is clear enough. Put the blinders on. Focus on your temple.