Cold Water Spring State Preserve is a 60-acre (240,000 m2) parcel state preserve protecting a spring that issues from Cold Water Cave, an extensive cave system in Winneshiek County, Iowa and Fillmore County, Minnesota.
The spring is a tributary of the Upper Iowa River.
The cave system contains a large underground creek that courses around much of the cave's nearly 16 miles (26 km) of passages.
Coldwater Creek Wildlife Management Area is a state hunting ground near Bluffton, and is near to the cave system.
The cave is located in the Driftless Area of Iowa and Minnesota, a region characterized by karst topography, which involves disappearing streams, blind valleys, sinkholes, caves, cold springs, and cold streams, all of which are present here.