(Radio Iowa) – A team of University of Iowa archaeologists is investigating a network of tunnels beneath Iowa City which were once used by the Union Brewing Company to ferment beer and transport it to taprooms connected by the caves. Researchers are using specialized radar equipment to search out the contours of yet-undiscovered tunnels to get a better sense of the cave system. Doug Alberhasky, the owner of John’s Grocery, is leading tours of one section of the caves.

“You can see that there are tunnels going every which way,” he says. “There was a tunnel going right there at one point. So this is a very large complex and unfortunately, we probably only have about a third of it that we are going to be able to see.”

There’s about four-thousand square feet now open. U-I archeologist Marlin Ingalls says stable subterranean temperatures combined with a little ice from the Iowa River were a winning combination for brewers who needed consistently cool spaces to make lager beer.

(by Zachary Oren Smith, Iowa Public Radio)