The Green Mill was a speakeasy during prohibition and has also been featured in movies; the one I half remember it gets blown up. So it is fairly called legendary.
Now it is a venue for jazz most nights and also hosts the long running poetry slam. This place has a classic lounge look to it, and serves the usual mix of drinks.
The problem for me has been that the ventilation is pretty poor so it gets filled up with second hand smoke pretty quickly. This drives me out; I have a limited tolerance for other people's smoke.
If you can handle the smoke, it is a great authentic environment to hear some good Chicago jazz or some rowdy poets.
http://www.greenmilljazz.com/
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