Cummingsville Formation
Stratigraphic range: Ordovician
Cummingsville Formation in Decorah, Iowa. The Cummingsville is the brown upper unit; the Decorah Shale is below.
Type	Formation
Overlies	Decorah Shale
Location
Country	United States
Extent	Iowa and Minnesota

The Cummingsville Formation is a geologic formation in Iowa and Minnesota. It preserves fossils dating back to the Ordovician period.

• List of fossiliferous stratigraphic units in Iowa
• Paleontology in Iowa

• Various Contributors to the Paleobiology Database. "Fossilworks: Gateway to the Paleobiology Database". Retrieved 17 December 2021.