COMMENTS
Wow, that is an incredible circle. I may have to visit this one!
Hi I found a few circles myself near Area 51 don't know what it is!!
Google earth has a history slider in the view menu. check it out. These markings appear to be created after 1994. and before 2001, probably by some dipstick on a ATV.
what you see in the large circles is an easy thing to answer they are old pow wow dance and camping sites i know I'm one forth La'kota .
What are these big rings? Many of them in this area of Oregon. Farming? But why circular?