I visited the America's Stonehenge website after reading Colavito's posts, and noticed the claim that
" . . . America's Stonehenge is most likely the oldest man-made construction in the United States (over 4000 years old)."
The claim of "oldest construction" is a bold one. It's also wrong.
I sent the following email to Mark Eddy, the America's Stonehenge publicist, this morning:

I read with interest your exchange with Jason Colavito about what you claimed were “inaccuracies and omissions” in his review of an episode of America Unearthed that referenced America’s Stonehenge.
After looking at your website, I wanted to point out that the claim that America’s Stonehenge is “most likely the oldest man-made construction in the United States” is incorrect. That statement, featured prominently on your website, is not even close to being true.
Even if we accept that the stone constructions are “over 4000 years old” (a claim of which I am extremely skeptical), an age of around 2000 BC would not make these structures the oldest in the United States.
Careful archaeological work has demonstrated that Archaic peoples were building earthworks in the Southeast at least as early as 3500 BC. I refer you to information about the Watson Brake mound complex in Louisiana, perhaps the best-documented case of Middle Archaic mound-building in the United States [image source]. Arguments have been made that other artificial mound constructions in the Southeast may pre-date Watson Brake by a thousand years. Either way, it’s clear that people were building large scale structures in the United States well before 2000 BC.
If we include above-ground structures such as houses, there are many documented examples of “man-made construction” that pre-date the 5500-year-old monumental earthen constructions of the Southeast. Remains of wooden post structures dating to the Paleoindian through Middle Archaic periods (about 11,500-3,800 BC) have been documented in Illinois, Georgia, Wisconsin, Maine, Virginia, and Mississippi. I refer you to my online database of prehistoric houses for information about those.
Finally, I would like to mention the recent, widely-publicized claims for the existence of 9,000-year-old stone hunting structures beneath the waters of Lake Huron. If the dating and the interpretation are correct, those constructions pre-date 2000 BC by five millennia.
Even in the best case scenario, the constructions at America’s Stonehenge are nowhere near the “oldest man-made construction in the United States.” I hope that you will consider the direct evidence of numerous artificial structures in the United States that pre-date 2000 BC and take steps to correct the statements that appear on your main page as well as your Facebook page.
Respectfully,
Andy White"