Visit the stunning crystal formations of Crystal ... The cave opened in 1932, making it the longest-run show cave in Iowa. Crystal Lake Cave is open on Saturdays and Sundays from 9 a.m. to 5 ...

And if that wasn't enough of a draw, Maquoketa Caves is completely free to enter! Read more: All Of The US National Parks That Are Free To Visit Year Round Iowa is not exactly high on most people ...

Fluorescent cave minerals are helping scientists explore how life could survive in harsh places like Europa. Far beneath ...

Astrobiologist Joshua Sebree of the University of Northern Iowa suggests that South Dakota's Wind Cave exhibits chemical ...

Scientists from the University of Northern Iowa explore caves and map the colors emitted by the rocks in different locations. The group is building a library of calcite fluorescence to share with ...

An Iowa city is ... trails throughout Ice Cave State Preserve and Dunning Springs, but because of their complexity, they often are not marked on maps, according to Visit Decorah's website.

Fluorescent caves on Earth may hold the secrets to survival necessary for scientists to detect life elsewhere in the universe.