Few people know about the old caves and tunnels beneath Iowa City, and why should they? Buried beneath streets, buildings and houses all around the older parts of town, they pass both from view and general knowledge. The city engineer’s maps won’t show all the caves and tunnels, nor the extent to which they wind through the ground beneath our city.
Built of stone or brick, these caves and tunnels provide much of the basic subterranean infrastructure for Iowa City. Three methods were used to build these structures. The first was the stone box method that used 6-feet square limestone slabs to make tunnels. The second was the voissoir arch method used in beer caves and root cellars. The third was a cut and quarry excavation into cliffsides.
Starting in the late 1830s many houses and businesses (such as John’s Grocery) had cellars built. Before the days of refrigeration these cellars were used to store root crops, fruit barrels, crocks of sauerkraut, pickles, preserves, cheese and other food. Many are scattered around town on private property, and a few are even rumored to have been used by the Underground Railroad prior to the Civil War.
For the beer caves, the voissoir arch method developed by the Romans was employed. Often built by immigrant laborers of Irish and Welsh descent and overseen by German master masons, construction started with a cut-and-fill method of digging a deep trench or open excavation cut down to the bedrock. Then the floor was leveled. The removed stone was used to build the beer cave’s vertical walls and the building’s foundation. The voissoir arch used wedge-shaped stones set with a keystone in the middle to create the ceiling of the cave. When finished, the building was constructed on top.
In the early 1850s, three large breweries were built along the 300 block of East Market and the 200 block of Linn: Great Western, Old City and Union. Only the 1855 Union Brewery (Brewery Square) still stands. The nearby Great Western and Old City breweries stood across from each other on opposite sides of the 300 block of East Market. The Great Western Brewery burned in a gigantic (and suspicious) fire in 1903. Englert’s 1852 Old City Brewery was razed for urban renewal. Today, parking lots are in the place where these two breweries once stood: Great Western sat between The Bluebird Diner and George’s Buffet; the City Brewery was between The High Ground Cafe and El Banditos Restaurant.
Beneath all three former breweries lie extensive beer caves that are construction marvels. They’re still present underground along with lost tunnels leading to nonextant buildings. The Brewery Square beer caves are still accessible and once consisted of three subterranean levels. The entrances to the Great Western and City Brewery caves have long been buried. At one time a beer tunnel ran beneath East Market Street from Brewery Square to their tavern in the old hotel (the Haunted Bookshop). Despite long standing rumors, none of these beer caves extend to the river.
Near the eastern end of Park Road Bridge, the 1850s Englert ice caves once stored river ice. Delved into the stone cliff face, they are rumored to be large enough to turn a truck around inside. The Englert’s old house north of Mayflower Dorms also operated as a hotel and tavern. While not truly “lost,” these caves have been closed off for over 50 years.
Beneath older parts of Iowa City are extensive drainage tunnels as well as sidewalk and steam tunnels that were built in the 1850s and 1860s. A Civil War era 6-foot-tall brick tunnel runs from the hill crest north of Brown Street, under North Market Park, through a buried ravine to Mercy Hospital where it intersects a 5-foot-square, 1850s stone box tunnel that heads west to meet Trowbridge Hall. Past Trowbridge it runs all the way to the University power plant at the Iowa River. This tunnel branches off and is known to lead to a grated entry shaft at the back of the State Historical Building. A once-lost branch of this tunnel was recently discovered during remodeling under Stuit Hall on Jefferson Street.
Beneath the sidewalks downtown, another extensive tunnel system exists. From the 1850s to the 1930s it serviced the lower levels of businesses through cellar doors that led to iron hatches set into the sidewalk. Operational sidewalk lifts are still present downtown between Clinton and Dubuque Streets and Iowa Avenue and Washington Street. In front of the west side entry of U.S. Bank a small metal grated tunnel entry shaft with ladder descends a distance of 10 to 15 feet. Other tunnels exist, too: the brick steam tunnel running beneath Gilbert Street from the Close Mansion to the old paint factory near The Vine. The longest tunnel system lies beneath the UI Hospitals. With branches to several buildings, it is still used daily by hundreds of people.
Urban caves and tunnels are extremely dangerous and not places to explore. Wisely, the city, businesses and the University have barricaded access to these hidden realms. No, there are no skeletons but some interesting graffiti exists along with remnants of past use and occupation. The University’s steam tunnels are so hot a person would quickly perish. These places are remnants of the city’s past and for many evoke thoughts of Industrial Archaeology.
During the Northside BrewFest, attendees will have an opportunity to win a visit to the beer caves under Brewery Square through a raffle held at the local history tent. There are conditions though: One needs to weigh less than 250 pounds, be unaffected by heights, depths, the dark or claustrophobia, and be able to descend and ascend a 25-foot ladder.
Marlin R. Ingalls is a professional archaeologist, historian and architectural historian within Iowa’s Office of the State Archaeologist. He is a member of the state historical society of Iowa’s Technical Advisory Network and former member of the Iowa’s State Nomination Review Committee, which reviews nominations for listing on the national register of historic places. He is also a consultant specializing in helping preservationists and communities evaluate, document and restore their historic buildings, neighborhoods and other historic resources.