And looking back into the observation room. That's the same pedestal on the right. You need to almost crawl out, and watch your head, that's solid concrete above. The round well would have been an observation post, and the opening in the front rim was almost certainly cut out when the trail to the top was built. The original access to the top would have been by the ladder in the stairwell. You can see the edge of another round observaion post on the left edge of the photo, that's the one that showed a few photos back.
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