At the bottom left, you can see Mulholland with one of his mirrored figures. These figures are featured in many of his pieces.
Vestige wasn't originally intended as such, but hikers liked it so much that it's become a permanent exhibit. You can still see it today if you're ever in the woods in this area of the world. As for Mulholland, he's been creating installations and sculptures since, and has had recent exhibits throughout Europe and in Korea.