If you're planning a trip to the United States of America, it's worth considering the dates of the American public holidays.
The USA has eleven Federal holidays - ten that are annual and one that happens every four years (Inauguration Day).
In general, when a holiday falls on a Saturday or Sunday the holiday is usually observed on Monday (if the holiday falls on Sunday) or Friday (if the holiday falls on Saturday).

Ultimately, it is up to each state to decide whether, when and how each of these Federal holidays is observed.
In addition, individual states have their own holidays such as Alaska Day, Truman Day in Missouri, Good Friday in Louisiana, and Mardi Gras in several states including Mississippi.

Unlike in many European countries, the United States are fairly relaxed about observance of these holidays. Most retailers, for example, are closed only on Thanksgiving and Christmas, whilst private businesses often only observe the so called "big six" holidays (New Year's Day, Memorial Day, Independence Day, Labor Day, Thanksgiving, and Christmas).

American Public Holidays