So on Friday (June 13) some of my co-workers (JessalynnRose) and I went to the Milwaukee County Historical Society, located at 910 N Old World 3rd St. There is a $5 admissions fee. It was very interesting learning about how it used to be a bank and how the structure of it was rebuilt over the years. Above is a picture of the lobby and below is a vault that was used.
This was how it looked like for the vault's lock.
This was what it looked like inside the vault, although the inside of the vault usually varied. Also fun fact: Johnny Depp used this exact vault in his movie Public Enemies. It wasn't a very long scene, but the amount they paid to be able to shoot in this vault was enough to help pay for the restoration of the ceiling of the museum (below).
I would recommend to everyone to go and check it out and go on a little tour. Especially if you like learning a little history and want to know how Milwaukee came to become a city, they have a little information on Milwaukee's founding fathers as well.