Monument Rock, a Vernon County rock spire
On our travels last week, while driving on Hwy. 82 East in Franklin South of Viroqua, Wisconsin, we came across this rock feature that had a Hwy. sign labeled 'Monument Rock'. Catching our attention, we stopped and marveled at its stature wondering what made this feature that stands out among the plateau of farmland. In our initial research, we found very little about it. After a short post on our Facebook page, and asking for any information on this amazing rock feature, Prairie Du Chien resident Phil Burgess posted an intriguing background on Monument Rock.
According to Burgess’ post, Monument Rock is an erosional remnant of Ordovician-age St. Peter Sandstone located on a sandstone ridge along Hwy. 27/82 E in the Town of Franklin, Vernon County. Burgess continued, it formed by the prolonged piecemeal erosion of the surrounding rock over many thousands (to millions) of years. This is a sign of the "true Driftless" region, as any ice sheet would have destroyed this delicate rock spire. Chimney Rock is another example, and others are known in the region.
So, there you have it. We hope that anyone else that may have been quizzical after seeing this rock spire may now sleep at ease.
Our gratitude to Mr. Burgess for sharing his knowledge.