Mt. La Grange – Barn Bluff
This bold bluff was a landmark for French explorers who named it Mt. La Grange for its resemblance to a large barn.
Some 10,000 years ago meltwater from the glaciers carved a deep channel in this area. Barn Bluff became an island in the five-mile wide river that then filled the valley.
The rock layers are shown at the left. The nearly vertical fault line visible at the bluff's southwest edge indicates a crack which developed millions of years ago. As a result the greater part of the bluff on the river side dropped 150 feet, leaving the bluff dolestone adjacent to the green sandstone at the fault line.
The bluff is 3100' long, 800' wide, 334' above the river and 1001' above sea level.
Limestone was quarried out of the Oneota stratum for about 40 years until stopped by citizen protest in 1908. In 1910 Barn Bluff was donated to the city for a public park.
Marker can be reached from East 5th Street ½ mile east of Bluff Street, on the left when traveling east.
Courtesy hmdb.org
