What you should know about the historic Miller Caves in Milwaukee

They might be the best-known basement in Milwaukee.

The Historic Miller Caves, part of the Molson Coors (formerly known as Miller) brewery complex in Milwaukee, date back to 1850. They haven't been used for their original purpose for more than a century, but they still get plenty of traffic: For decades, the caves have hosted celebrities and special events — including a featured role in an episode of "Top Chef: Wisconsin."

Here's what you should know about the Historic Miller Caves in Milwaukee.

Where are the Historic Miller Caves?

The caves are in the Molson Coors brewery complex at 3897 W. State St. in Milwaukee.

Are the caves natural or human-made?

They are human-made, carved out of limestone cliffs in the Menomonee River Valley.

Who built the Miller caves? What were they built for?

Charles and Lawrence Best — sons of Jacob Best, who founded what became the Pabst Brewing Co. — owned the Plank Road Brewery built along what is now State Street. A year after the brewery opened, the Bests had workmen carve caverns out of the nearby limestone to create space to keep their beer cool. Frederick Miller and his family purchased the brewery five years later, in 1855, and expanded them to keep up with Miller's rising production.

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When were the caves closed down?

Miller Brewing continued to use the caves as refrigerated storage space until 1906. By then, mechanical refrigeration was a better and more efficient way to keep beer cool. Miller officials had the caves closed up, although sometimes celebrity visitors were brought in to check them out for a photo-op. (For example, Lawrence Welk, leader of one of America's biggest polka bands of the postwar period, stopped by the caves in 1949, as part of a promotional visit to the brewery. Miller was sponsoring the bandleader's radio show at the time.)

And there may have been other visitors to the caves. Paranormal Investigators of Milwaukee lists claims of sightings of several ghosts — including the apparitions of a young 19th-century brewery worker and his sweetheart.

When were the caves reopened?

The Miller caves remained boarded up until 1953, when they were "rediscovered" during other building projects on the Miller campus. Frederick C. Miller, the brewery's dynamic boss in the 1950s, decided the underground space would make a good museum. Exhibits illustrating the brewery's history were fashioned for a portion of the caves and they were reopened to the public in a fanfare-filled event on Oct. 19, 1953. The guest of honor for the event was Milwaukee's biggest celebrity of the age, Liberace.

Can you visit the Miller caves today?

For decades, the entrance to the caves was the starting point of Miller's popular brewery tour. It's still an important stop (and in summer, one of the cooler ones) for the tourist attraction. The caves, which went through extensive renovations in the early 1990s, are also available for rental for private events. Molson Coors says the space has room for 40 (seated) to 100 (standing).

Sources: Journal Sentinel archives; "The Miller Beer Barons" by Tim John; "Miller Time: A History of Miller Brewing Company 1855-2005" by John Gurda

This article originally appeared on Milwaukee Journal Sentinel: What you should know about the historic Miller Caves in Milwaukee