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< McGregor's 19th Century Refrigerators

Red ball iconMcGregor's 19th Century Refrigerators

by Robert M. McKay


The McGregor area of Clayton County in northeastern Iowa is known for its rugged bluffs along the scenic Mississippi Valley and its well-preserved 19th century architecture. In the days before refrigeration, the town's early residents made innovative use of the bedrock geology composing these bluffs.

The 400-foot descent along the main highway into McGregor passes through numerous rock outcroppings of 450 to 550 million-year-old limestones and sandstones (Ordovician and Cambrian; see Bedrock Geology map of Iowa) to the town's flat valley floor. Of particular interest to residents during the steamboat era were two prominent sandstone layers that outcropped in the valley, rock units now referred to as the St. Peter and Jordan formations. Residents found that the unusually soft, uniform "sand rock" was easily excavated with hand tools, and that "caves" or "cellars" carved into these sandstones provided ideal space and cool temperatures for refrigeration and storage of river ice.


Excavated cave Excavated cave Excavated cave

Photos by Pat Lohmann.

These entryways were hewn into bluffs of Jordan Sandstone at McGregor, Iowa, and opened into caves excavated for cold storage. In addition to brewery cellars (photos, above center and right), 20 tons of ice were once stored in the cave at below center (former site of the popular "Mississippi House" hotel and tavern), and the brick-lined cave (below right) functioned as a cistern for water storage.


Excavated cave house   Excavated cave   Excavated cave

Photos by Robert McKay.

Most of the cellars were carved into the Jordan Sandstone along the northern end of Main Street, where hotels, taverns, and apartment buildings backed into small courtyards framed by the nearly vertical sandstone bluffs. The cellars varied in size and were entered via arched doorways. Smaller caves, typically associated with taverns and apartments, were about 20 feet deep and housed items ranging from food to ammunition. One building even had two second-story caves (photo, bottom left), with one connected to the balcony by a catwalk. Larger, multi-room caverns were excavated for business interests, especially breweries. For example, the once-flourishing J. L. Hagensick Brewery, built in 1845 between McGregor and Marquette, had four cellars cut into the Jordan Sandstone (two photos shown, top center and right) where most of its 10,000 barrels of annual production were cooled and aged.

Two miles south of town, the St. Peter Sandstone was also used for cold storage. The present White Springs Supper Club was once site of the Klein Brewery, built in 1857. Three arched-ceiling caverns, 30 feet below ground level and each measuring 25 by 60 feet by 7 feet high, held casks of aging lager beer. The casks were slid down a steep stairway into the caverns, then floated in a spring-fed, water-filled trough to their storage locations.

Most of these historic caverns are now inaccessible because of the deteriorating effects of time and weather. As one strolls through McGregor, however, several sandstone entryways remain visible, reminding us of the interesting and historic influence of local geology on the lives of the people who lived there.


Adapted from Iowa Geology 1997, Iowa Department of Natural Resources