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Far back in the geological past, perhaps six or seven hundred million years ago, Wisconsin was part of a mountainous region which covered all this state and much territory outside it. It had peaks and ridges similar to those in the Alps. We know of this former mountainous condition from a study of the rocks and the topography of today. Remnants of rock folds reveal that there were once lofty ridges and deep valleys in northern Wisconsin. The types of the folds tell us that the ridges were parts of a mountain range more like the Alps or the Rockies than the Appalachians. The granites show that erosion has cut down to igneous rocks such as are formed only by deep- seated cooling of molten intrusives, often beneath the arch of a lofty mountain range. The gneisses and schists suggest the former presence of tremendous pressure and some heat. The trap rocks indicate that lava flows emerged at the surface in the later stages of the mountain history. The fossils in the overlying sedimentary rocks show that these mountains are among the oldest in the world. These lofty mountains were attacked by weather, wind, and streams, by solution underground, by plants and animals at the surface, as mountains are being attacked today. They were gradually worn down, till nothing remained but a low, undulating plain with occasional hills. This we call a peneplain. The destruction of the mountains took a long time, of course, but time enough was available. The rivers carried sand and mud and dissolved mineral matter from the mountains into the sea. There it was deposited as sandstone, shale and limestone. The mountains were uplifted again and worn down again, repeating this history several times. Eventually, Wisconsin and the adjacent region sank beneath the ocean, probably remaining submerged for long ages. While it was sinking, the hills that rose above the surface of the peneplain may have been little islands in the sea for a short time. Waves may have beaten against their shores, making beaches. Subsequently it was uplifted and submerged several times. Two hundred million years or so ago this part of the United States was uplifted for the last time, and has since remained dry land. The peneplain on the site of the ancient lofty mountains of Wisconsin was completely hidden beneath the limestones and sandstones. The work of weather and streams recommenced, and continued till the state was fashioned into something similar to its present form. Throughout all parts of Wisconsin except the Northern Highland, the Baraboo Range, the Barron Hills and such places, the worn- down pre- Cambrian mountains lie deep beneath the present surface. In the northern part of Wisconsin the worn down mountains have been revealed. We know the visible portion of these worn- down, buried and exhumed mountains as the Northern Highland of Wisconsin. Bill

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Q: Are There mountains in Wisconsin I am from Colorado I say no way hills yes Mountains NO?
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