As I understand it the Green Door Tavern is one of Chicago's oldest standing bars. This is easy to see when one passes through the front door, slanted from years of settling and shifting. The bar/dining room is full of antique junk and everyone seemed very friendly. They also have a signature drink called the French 75 which is made from gin and champagne and a couple other ingredients. I don't recommend it unless you are a gin fan, but "when in Rome," right? The GDT is hiding a much bigger secret, though. It was once home to a speakeasy which still exists and functions somewhere in it's bowels if you can find it. Or, if you can't the bartender will tell you.