http://www.crystallakecave.com/

Iowa’s largest show cave

Spook Cave

Cliff Dwellers

Cliff Dwellers

Cave of the Mounds

Soda straws

Soda straws

Crystal Lake Cave 2016

Crystal Lake Cave 2016

The Wild Tour 2016

The Wild Tour 2016

3-amigos

Some of the many crystal formations inside this cave

lost-gardens

Lost Gardens

More beautiful formations

More beautiful formations

The wedding chapel

The wedding chapel

The Glacier

The Glacier

This one is from the Wild Tour

This one is from the Wild Tour

This cave is breathtaking

This cave is breathtaking

The lake for which the cave is named

Crystal Lake inside Crystal Lake Cave

Louisville Mega Cavern

Love this picture, from Matthison State Park

Another from Matthison State Park

Under ground tunnel

Cave of The Mounds

La Jolla Sea Caves

Kentucky Mega Cavern

Kayaking through a Sea Cave

Sea Cave

Maquoketa Caves State Park