THE TREES HAVE EYES! Clear the lower branches from a thicket of trees and go nuts! If you paint them really big, they could work along the trees on the dam wall because people view them from afar. Use glow in the dark pink paint!
When I think of places that are associated with Transcendentalism, I think of places like the woods. Just areas with no cities around that are full of places to explore. The forest is just a great place to lose yourself in nature.