The Highland Passage stone chamber. A few years ago, I was able to walk inside this stone chamber, but it has since caved in. (The third photo has been brightened to show the interior.)
Highland Passage Stone Chamber, Putnam County, NY 5/2/15 Copyright © J.L. Jarvis 2015
Highland Passage Stone Chamber, Putnam County, NY 5/2/15 (Second image has been brightened to show interior.) Copyright © J.L. Jarvis 2015