Google Earth -- Is this an ancient impact crater?

I was exploring southern New Hampshire with Google Earth and came across this structure [Google Earth required] in Pawtuckaway State Park that looks strikingly like the ancient remains of a terrestrial impact crater about 1 mile across, with a central peak. But I looked it up on The Earth Impact Database, and it is not listed. So is it just a coincidentally round structure, or might it be a previously undiscovered impact crater?

If it is, do you get to name it??

It looked like an old caldera to me, and a bit of googling about suggests that Pawtuckaway had volcanic origins:

http://nhgeology.org/jurassic.htm

From the section on ring dikes.

Google Earth community has a tag which says the following :

Agrees with yabob’s post.

Thanks yabob, ring dike it is. Armed with the correct term, I have found lots of information on Mt. Pawtuckaway. I may take a drive up there this weekend and check it out. Based on my atlas, there is a road that circles between the outer ring and the central peak, called Middle Mountain, as well as a picnic ground and old Chase Cemetary. Looks cool.

A few years back, they repaired the road and extended it so you can now take your car almost all the way through protect away reserve but by round pond in the middle of the reserve the pond sometimes goes over the road and that sometimes of the year could be up to 4 to 5 feet over the road so you would have to stop halfway through the road but that’s a wonderful area to take a picnic.
I strongly recommend bringing a kayak or canoe with you and exploring the island in the middle of the pond. It’s amazing back there. It has a little cave in it and it’s a wonderful place to camp.