Seems huge and at the same longitude of Giza Pyramids in Egypt, but it lies on Ocean sea floor in the Bermuda Triangle, just off coasts of Georgia and Florida. After reading an interesting thread on an archological discovery of the remains of an ancient walled city which predates the construction of Egypt's pyramids off the Georgia coast, I dug up a bit nearby the Atlantic East Coast http://pubs.usgs.gov/of/2010/1332/ht..._overview.html
Using GLORIA a long-range sidescan sonar system GLORIA (Geological LOng-Range Inclined Asdic)
on the bottom left, I found this...
Something like a Pyramid
It's awesome, but, of course, this deserve a more accurate and deeper analisys