Aztalan State Park is a Wisconsin state park with pyramids

Wisconsin United States
Aztalan State Park is a Wisconsin state park

pyramids

is believed to the site of an ancient city where citizens from Atlantis mined copper and shipped it to Europe.The mystery came to light in 1835 when
pioneers settled the south-central part of the state. There they discovered the remains of three flat-topped pyramidal mounds and many smaller
artifacts scattered throughout the surrounding area. Initially, settlers referred to the three truncated earthen pyramids as the "Ancient City." Soon
thereafter, however, Nathaniel F. Hyer, a judge from Milwaukee with an interest in ancient matters, re-named the site "Aztalan" because of its
resemblance to a place described in an Aztec legend.

Since 1835, archaeologists have learned that the people of Aztalan may have been related to the inhabitants of Cahokia, a similar but much larger
settlement in southwest Illinois across the Mississippi River from St. Louis. . Further research has revealed that at one time Aztalan covered 21
acres and had a population of approximately 500Rock Lake, Wisconsin is reported to have an ancient pyramid submerged in its waters.
Sauk Native Americans speak in their legends of a sacred site close by a lake. The Sauk did not construct the site and related structures - this was
done by ancient peoples who were driven away when the lake flooded. Stories have continued to the present concerning Rock Lake "pyramids" and
other underwater foundations.
The "pyramid" legends were revived during the mid 1930s when a combination of low water and clear, dry summers allowed viewing of a number of
subsurface geometric forms including pyramids, cones, walls, and trenches. One individual Max Knoll, using his own invention - a form of SCUBA
dive gear - dove the lake and viewed many of these structures. Still, those who supported the theory of man-made underwater structures were
ridiculed and little was proved either way.
Interest in the structures was renewed when observations of SCUBA divers were published in the 1960s. A major effort commenced in the 1980s
with a complete side scan sonar study of the lake floor showing a number of unusual-shaped structures along a submerged beach.
Side-scan sonar reading, indicating several artificial structures beneath the surface of Rock Lake.
Unusually clean water conditions in 1991-92 allowed two of the sites to be photographed in sufficient detail to prove their existence as man-made
structures. Sufficient evidence does not exist to date the structures or to identify their builders. One possibility is that they are associated with
prehistoric copper trade cultures which would coincide with the Post Algoma low lake levels of 3,000 years ago. Future research will hopefully tell us
more about these ancient visitors and their contributions to Wisconsin heritage

45 miles west of Milwaukee, over 800 years ago, a walled pyramid city flourished , appearing to have succumbed to the black side of Cthulhu as
their citizens dissolved into human sacrifice and cannibalism, culminating in the destruction of their great ceremonial center around 1325AD

http://www.burlingtonnews.net/wisconsinvortexs.html

https://en.m.wikipedia.org/wiki/Aztalan_State_Park