Banks typically close on all of the following holidays: New Year's Day, Good Friday, Memorial Day, July 4th, Labor Day, Thanksgiving Day, and Christmas Day.
Outside USA, probably none. Countries are by and large proud of their own currency and require foreign visitors to buy it in banks or bureaux de change.
Saturday is considered a weekend day in the U.S. Saturday is famous for marking the first day off from a regular job, and pretty much every person who works a standard job (5 days a week, 9 a.m. to 5...