There is a "string swing" jam every Wednesday at McGraths Irish Pub in Alameda, CA. Starts at 8:00 PM and ususally ends before Midnight. There is a jam leader but it is pretty loose. Friendly, encouraging atmosphere. Tunes generally played are standards (Lady Be Good, etc) and western swing. Over 21 only. Here is a web site for McGraths.
http://www.mcgrathspub.com/
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