The term "mound" in Wisconsin refers to any isolated hill. Flickr pictures here.
Central Wisconsin was once covered by Glacial Lake Wisconsin. Glacial Wisconsin . Huge lakes were formed when glaciers, and their deposites, blocked natural drainages. As the glaciers retreated northward, many of the lakes drained and left broad, flat lake beds which are now rich agriculture lands and large marshes providing rich habitat for birds and other wildlife. In some of the deep gorges and valleys, populations of plants associated with cooler northern climates still persist.
The extensive waterways left by the glaciers provided easy transportation routes as well as homes for fish, fowl, and animals which attracted early explorers. Forests across the land provided timber which was harvested and shipped along the waterways.
This is the Ice Age Trail. For unkown reasons, southwestern Wisconsin escaped glaciation. Known as "the Driftless Area," it is a low plateau deeply cut by stream valleys. It is an old landscape whose rougher surface contrasts with ice-formed topography. astellated buttes, spires, and pinnacles were sculpted by Glacial Lake Wisconsin breaking on sandstone outliers of the Driftless Area.Drumlins, kames, eskers, kettles, and moraines are now protected in the Ice Age National Scientific Reserve and offer a great introduction to Ice Age geology. The Ice Age Reserve consists of nine units across Wisconsin. By car you can visit more than one unit a day ie: Horican Marsh, Kettle Moraine, and Cambellsport Drumlins; or Devils Lake and Mill Bluff. Hiking trails are now open and are being marked. (6)
This is a picture of Rattlesnake Mound. The topography in northwestern Illinois, southwestern Wisconsin, northeastern Iowa, and southeastern Minnesota is very different from the rest of the Midwest. 
(Rattlesnake Mound)Bluffs, sandstone mesas, and forested mounds are amazingly found all within hours of Chicago.
The mounds of Central Wisconsin were once much like the Fiji Islands..... the glacier must have removed hundreds of outlying mesas and buttes, and thousands of smaller pinnacles similar to Stand Rock (pictured).....
Before the Glacial Period these rock formations must have existed in vast numbers throughout the whole Central Plain. Where the weak sandstone lay in the direct path of a rapid current of the glacier, the ice eroded deeply and scoured out lake basins. 
The mounds of Central Wisconsin were once partly submerged. Today, the castle-styled mounds and isolated hills of Cambrian sandstone are found rising steeply above the central lowlands of Wisconsin, and are occasionally capped by Ordovician dolomite. Usually, they simply consist of sandstone, and are often steep-sided pinnacles. They are far too delicate to have survived glaciation, and many owe their steepness to wave erosion by Glacial Lake Wisconsin. They will be gone in a few tens to hundreds of thousands of years. 
Roche-A-Cri is the sheerest cliff face in Wisconsin. A view from its 300' overlook spans 120 miles.
Eventually, as the resistant cap is removed by weathering, the buttes soon wear down to conical hills. The capping material which forms the flat tops of these buttes and mesas is one of several resistant sandstone layers, which is better cemented than the average.
This is a view from Friendship Mound overlooking Friendship Lake. Because the rock is porous, lacks limy and shaly beds, and it has a thick-bedded character, we find the soft, weak Cambrian sandstone is able to stand up in cliffs, irregular crags and tower formations.
This is a view of Lone Rock from Rattlesnake Mound in Adams County. Adams County, WI is located in the Heart of Central Wisconsin and has 23 well known rock formations.
Easton Mound: Adams County, WI . Weathering and wind work are going on rapidly around the borders of these tabular hills. The sandstone breaks down along vertical joints, the rock falls to pieces, and is blown and washed away. 
While paddling the Upper Wisconsin River you can see Elephant Back Mound just to the left of Louis Bluff in the faint distance.
This is Elephant Back Mound in winter( Snowshoeing )just off of 13 on the east side of the road near the Chula Vista Resort.
Ground and end moraines, drumlins, and erratics are all features that were depostied by the ice itself--not by meltwater. The materials that compose them were not sorted by the action of moving water. Ground moraines were deposited under moving ice, or were just let down in carpet-like form as stagnant ice melted. End moraines are merely glacial dumps from the edge of moving ice and are usually perpendicular to the glacier's direction of flow.
There are three types of end moraine: 1) Terminal moraines are the outermost end moraines of the glacier's advance and they mark where the glacier ended, 2) Recessional moraines are those left by retreating ice, 3) Interlobate moraines are built between lobes of ice. Erratics are rocks carried from a distance inor on the ice.
Drumlins were built up in layers beneath moving glaciers and usually occur in groups up to hundreds behind the end moraines. It's long axis parallels the glacier's direction of flow and it's appearance is described as halves of teardrops. (6)
This is Rock Springs. Located in Wisconsin's Columbia and Sauk Counties. The range is an example of a buried mountain range exposed through erosion, to once again undergo the forces of surface erosion. Consisting of highly eroded Precambrian metamorphic rock, the Baraboo Range is considered a "monadnock" which is an erosion resistant isolated hill.
Rock Springs is part of the Baraboo Range which is about 25 miles long and varies from 5 to 10 miles in width. Map by Steven Dutch, Natural and Applied Sciences, University of Wisconsin - Green Bay . (1) Adams County Rock Formations, Cliffs, Mounds, Bluffs & Rock Outcropping in alphabetical order. (5)
WORK CITED
1. Steven Dutch, Natural and Applied Sciences, University of Wisconsin - Green Bay
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