Steven Dutch, Natural and Applied Sciences, University
of Wisconsin - Green Bay
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Contrary to popular misconception, the bluffs never "used to be in Minnesota." It's true that the Mississippi channel once ran north of the bluffs and they were attached to the bluffs on the southwest side of the present river. If the Mississippi hadn't changed course, and the state line followed the river, then the bluffs would be in Minnesota. And if the North Atlantic had opened differently, New York would be in Morocco. So what? The state line has always followed the present course of the river, and the bluffs have always been in Wisconsin.
How exactly the bluffs came to be separated is something of a mystery. There are no hanging valleys along the Mississippi, so the stream profiles suggest that the streams had already cut downward fairly close to present river level before the river changed course. With a wide, well-established channel to the north and east, why would the river have cut through the bluffs?
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Looking northwest from north of La Crosse. The bluffs of Perrot State Park are right of center above the trees in the middle distance. |
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Looking west across the Mississippi to Minnesota |
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Views from the lock and dam just south of Trempeleau. The next four views look north toward Eagle Bluff. |
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The two views below are looking south |
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View of the lock and dam from Trempeleau. |
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Entrance to Perrot State Park |
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Trempeleau Mountain |
Below: Panorama of Trempeleau Mountain and the former Mississippi flood plain at right. The Mississippi River is visible to the right and beyond the mountain; the distant bluffs left of the river are in Minnesota, those on the right are in Wisconsin.
Below: Panorama of Trempeleau Mountain with distant Minnesota bluffs to the left.
| Cambrian sandstone along the river road | |
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| Horseshoe Falls (dry) | |
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View of the Mississippi River and Minnesota bluffs |
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Left and below: views on the lower part of the trail. The trail is described as a "natural terrain" trail and signs warn of it being difficult in spots. It would be easier if it were a bit harder instead of creeping uphill at a gentle grade. |
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Cambrian sandstone along the trail. |
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Near the top, the Cambrian sandstone becomes calcareous and has numerous round calcite concretions. Some of the elongate ones may be sand crystals. |
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A thin layer of Ordovician Prairie du Chien dolomite caps the bluffs. |
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Openings like this along the west side of the river bluffs are nicknamed "goat prairies." They owe their sparse vegetation to a dry setting due to the steep slope, porous rock and western exposure. |
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View south toward the Mississippi River |
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Perrot Bluff. Note the total absence of any provision for a
panoramic view. Below: Views inland are mostly obscured by trees. You have to wonder what is the point of having a trail here if there's no effort to open up a good view. Note the extremely wide abandoned flood plain. |
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Below: panoramic view of the Mississippi River
 | Looking southeast from the foot of Eagle Bluff |
 | Cliffs of Cambrian sandstone and Prairie du Chien dolomite on Eagle Bluff. |
 | Ruined building at the base of Eagle Bluff |
 | Old building in Trempeleau. |
 | Left and below: Looking southeast along U.S. 61 east of Winona. |
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 | Left and below: Trempeleau Mountain from the Minnesota side |
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 | Looking southeast toward Eagle Bluff |
 | Brady's Bluff |
 | Perrot Bluff |
 | Left and Below: Eagle Bluff with its prominent cliffs. |
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Below: Panorama of Trempeleau Mountain and Perrot State Park from the Minnesota side. The pictures were taken from different locations so foreground details do not align. Frankly I'm amazed the distant features align as well as they do.
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Created 23 August 2004, Last Update 16 September 2005
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