Originally Posted by 990 trailblazer
They are rivited steel plates as old boilers or tanks but are filled with concrete. You can see the concrete foundation with a short section of the support still embeded.
That makes sense. Looking at the picture again, I can see two of the larger diameter cylinders with a smaller diameter one connecting the two. I guess the way they have fallen over confused me... Oh, well mystery solved. Still can't wait to ride out that way again!