DSC09724-20180707: Cave of the Mounds, in Blue Mounds, Wisconsin
DSC09731-20180707: Cave of the Mounds, in Blue Mounds, Wisconsin
DSC09733-20180707: Cave of the Mounds, in Blue Mounds, Wisconsin, the bump running upper-left to lower-right is a fossil of a giant cephalopod sea creature which lived 450-500 million years ago
DSC09736-20180707: Oolites, or 'Cave Pearls', in Cave of the Mounds, in Blue Mounds, Wisconsin
DSC09747-20180707: Cave of the Mounds, in Blue Mounds, Wisconsin
DSC09749-20180707: Cave of the Mounds, in Blue Mounds, Wisconsin
DSC09780-20180707: Cave of the Mounds, in Blue Mounds, Wisconsin
DSC09788-20180707: Cave of the Mounds, in Blue Mounds, Wisconsin
DSC09793-20180707: Cave of the Mounds, in Blue Mounds, Wisconsin
DSC09801-20180707: Cave of the Mounds, in Blue Mounds, Wisconsin
DSC09829-20180707: Cave of the Mounds, in Blue Mounds, Wisconsin
DSC09849-20180707: Cave of the Mounds, in Blue Mounds, Wisconsin
DSC09858-20180707: Cave of the Mounds, in Blue Mounds, Wisconsin
DSC09860-20180707: Cave of the Mounds, in Blue Mounds, Wisconsin