Advertisement

Wisconsin Nature

Few People Know These Prehistoric Reefs In Wisconsin Are Hundreds Of Millions Of Years Old

By Nicole | Published March 10, 2018

Back during the Silurian Period, about 400 million years ago, this part of the country was covered by a shallow tropical sea. A reef collection formed that’s known as the Racine Formation. The limestone and dolomite bedrock of that was under that sea is what we still see here in southeast Wisconsin. It’s the reason so many quarries were formed here. Those shallow seas were very rich in marine life and the fossils that remain are in display in museums across the state. But you can also get up close and personal with them at the Soldier’s Home Reef near Miller Park in Milwaukee and Schoonmaker Reef in Wauwatosa.

On the near west side of Milwaukee, sitting right next to each other are the Milwaukee VA and Soldier's Home and Miller Park, the home of MLB's Milwaukee Brewers.

If you've ever driven along the road to the west of Miller Park, you'll notice that the road meanders a little bit.

Advertisement

You can see it here in the lower left-hand corner — those trees are growing on the Soldier's Home Reef.

Advertisement

These craggy, rocky cliffs are far more than they appear. It is the first geological reef formation described in North America, and it's among the first described in the world.

What remains is the lower 35 feet of a 70-foot high bluff that's about 450 feet long. The bluff is the only fully natural formation of its type remaining in Milwaukee County.

Over in Wauwatosa, in what used to be a lime quarry owned by the Schoonmaker, similar reefs were discovered in 1844. It is located North of W. State St., between N. 66th St. and N. 64th St. This picture dating to 1899 shows the quarry as it was then.

The exposed portion of the reef is in the Menomonee River valley in Wauwatosa. What you'll see is a large, rocky hill that runs for about 600 feet. The reef is about the bottom 20 feet of these bluffs. The layers above that were formed by glacial sediments left in the last million years.

Both of the reefs have been listed as National Historical Sites. Schoonmaker has tended to have more evidence of ancient life, but both are fascinating and easy to see reminders of the formation of our earth. From the reefs at the bottoms to the glacial sediment at the top, the layers of these bluffs carry hundreds of millions of years of history and information.

<span data-mce-type="bookmark" style="display: inline-block; width: 0px; overflow: hidden; line-height: 0;" class="mce_SELRES_start"></span><span data-mce-type="bookmark" style="display: inline-block; width: 0px; overflow: hidden; line-height: 0;" class="mce_SELRES_start"></span><span data-mce-type="bookmark" style="display: inline-block; width: 0px; overflow: hidden; line-height: 0;" class="mce_SELRES_start"></span>

Have you ever gone to explore these amazing formation in southeast Wisconsin? Let us know about it in the comments?

Interested in exploring more parts of the state that oh-so-gloriously show their age? Check out Amnicon Falls State Park, where the history is visible everywhere you look.

OnlyInYourState may earn compensation through affiliate links in this article. As an Amazon Associate, we earn from qualifying purchases.