I often go to the meetup in Kansai (http://hnkansai.org/), which rotates between being hosted in Kobe, Osaka and Kyoto.
The event space is anywhere that allowed us to use their space, usually some tech company office. We've had some gorgeous night views from a high-rise, cool atmosphere at the top floor of a hip bar, and admittedly the occasional small windowless room as well.
It's about 2 hours, starting 19:30 with introductions and two or three talks. After the talks people just chat with each other. Why are they "HN meetups"? People here have pretty similar interests, so if you give a talk or chat with someone about a topic that would interest HN, then it will probably go well at the meetup too.
Nothing for Downtown Minneapolis where I'm at. I might have figure a way to change that.