Crystal Lake Cave
Dubuque, IA, 50°F inside, from $22
A small city-run preserve with a cave whose walls and floor stay coated in ice well into summer. A steep stairway leads to a narrow passage that runs 120 feet into the bluff. Entry is free.
The story
The cave was shown commercially from 1929 to 1941, for 10 cents, or 25 cents with a guide. The city bought the bluff in 1954 with a gift from Jennie Edmunds Moss, and the site became a geological state preserve in 1973. The city of Decorah owns and manages it.
- Open to visitors since
- 1929
History source: iowadnr.gov.
Getting around underground
- The walk
- Steep stairs to the entrance, then a narrow, dark passage that can be icy and slippery.
Dogs, weather and what to wear
- Temperature
- Below freezing in the ice chamber until about midsummer
Good to know
- Best time to go
- Ice starts forming in March and is thickest in early June.
Getting there
Decorah Ice Cave State Preserve is in or near Decorah, IA.
Parking: Small parking area near the entrance.
- Madisonabout 121 miles
- Minneapolisabout 137 miles
- Des Moinesabout 152 miles
Distances are straight-line from each city center.
Questions people ask
How cold is it inside Decorah Ice Cave State Preserve?
Below freezing in the ice chamber until about midsummer.
Listed in: self-guided caves
Checked on 2026-10-23 against iowadnr.gov (Decorah Ice Cave State Preserve). Prices and hours change, so confirm on the official site before you drive out.