Native Winnebago or Ho-Chunk people have talked about a “sunken village of rock tepees” under Rock Lake since the early 1830s, when the first pioneers came in the southern region of Wisconsin between ― what is now ― Milwaukee and the capitol at Madison.
Until two duck hunters peeked over the side of their boat during a water-clearing drought at the start of the twentieth century, their legend was rejected as simple Indian fiction.
They saw a large pyramidal structure resting dark and enormous in the depths of Rock Lake. Since then, the buried construction has been shrouded in dispute due to deteriorating subsurface visibility aided by pollution.
Dr. Fayette Morgan, a local dentist and early civilian pilot in Wisconsin, was the first person to glimpse Rock Lake from above on April 11, 1936. He noticed the dark shapes of two rectangular structures on the bottom of the lake near its center from the open cockpit of his lanky biplane circling at 500 feet.
He made multiple passes and saw their regular proportions and enormous size, which he believed to be more than 100 feet apiece. Dr. Morgan landed to refuel and ran home for his camera, then flew off immediately to catch the sunken objects on film. The lake’s submerged monuments had faded in the late afternoon light by the time he returned over it.
Subsequent and repeated attempts to photograph or even rediscover them from the air failed until 1940 when they were discovered again by a local pilot, Armand Vandre, and his rear cockpit observer, Elmer Wollin.
But as their single-engine plane banked over the lake’s south end at less than a thousand feet, they were taken aback by a totally different sight. A massive, perfectly centered triangle structure pointing due north lay underneath them, under less than twenty feet of water. A pair of black circles stood next to each other towards the peak.
At least ten structures may be found beneath the surface of Rock Lake. Skin divers and sonar have mapped and photographed two of them. No. 1, named Limnatis Pyramid, has a 60-foot base width, 100-foot length, and a height of 18 feet, although only around 10 feet of it rises above the silty muck.
It’s a truncated pyramid made mostly of spherical, black stones. The stones on the truncated top are squarish. It is possible to see the remnants of plaster covering. The length of each of the delta’s equal sides was estimated by Vandre and Wollin to be 300 feet. A tiny, narrow buried island, maybe 1,500 feet long and 400 feet broad, lay northeast of the triangle.
More surprising was a straight path that ran underwater from the southern shore to the pinnacle of the buried delta. When Frank Joseph mentioned the observation to Lloyd Hornbostel, a local geologist, he thought the line was the remnants of a large stone canal that connected Rock Lake to Aztalan, three miles distant.
Aztalan is currently a 21-acre archaeological park with a stockaded wall that partially encloses the Pyramids of the Sun and Moon, two clay temple mounds. The ceremonial center was twice as massive at its heyday in the late 13th century. Then it had three circular walls with watchtowers enclosing a triad of pyramidal earthworks topped with wooden shrines.
Aztalan belonged to the Upper Mississippian Culture, which thrived throughout the American Midwest and into the South in its last stage, commencing approximately 1,100 AD, while carbon-dating experiments indicated its oldest known roots in the 3rd century BC.
Its population peaked at 20,000 people, who resided on both sides of the walls. They were headed by astronomer-priests who correctly aligned their pyramids for the calculation of several astronomical events such as the winter solstice, moon phases, and Venus locations.
Around the year 1320, the Aztalaners mysteriously set fire to their city, abandoning its flame-engulfed walls. They retreated far to the south, according to surviving Winnebago oral tradition. Their exodus happened to coincide with the abrupt development of the Aztec state in the Valley of Mexico.
“The finding of submerged buildings there may foretell a far larger one to come when we finally direct our study into the sea and probe its depths for the lost fountainhead of terrestrial civilization—Atlantis.”
Rock Lake is noteworthy for its buried stone structures ― pyramidal burial mounds of men who worked in Michigan’s Upper Peninsula’s copper mines from 3000 BC to 1200 BC. The mines were most likely dug and controlled by Atlantean engineers, therefore at least some of the underwater tombs include the bones of Atlantean laborers, according to Frank Joseph.