We went to Rainbow bar after a concert on a Monday night in July and there were not a lot of people there, mostly locals. But after 20 minutes and  3 times of attempting to get the bartenders attention had failed we walked out of this bar. . We had money and willing to spend it but apparently our money wasn't good enough for this bar. We went across the street to a bar called Railyard Ale House it was really nice and the drinks were great. Rainbow was awful I would say Railyard was a better choice and more beer selection.
Review Source:This is probably the best people watching bar in Billings. There is guaranteed to be at least 2 hobos in there at all times. I've seen a hobo who looks like a muppet in there get carried out by EMTs. I've seen a girl in a rainbow bright costume. The Rainbow is a loud and drunken good time, but don't go in there wearing your finest outfit asking for a martini. Also, it's cash only.
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