| 释义 | May 21
 May 21HolidaysAldersgate Experience (Sunday nearest May 24) May 21, 2017; May 21, 2023Anastenaria (May 21-23)
 Armed Forces Day (Third Saturday in May) May 21, 2011; May 21, 2016; May 21, 2022Celebrated in: Egypt, Honduras, Liberia, Mali, Myanmar, Sao Tome and Principe, United States
 Black Ships Festival (Third weekend in May in Shimoda, Japan; last full weekend in July in Rhode Island) May 21, 2011; May 21, 2016; May 21, 2017; May 21, 2022; May 21, 2023
 Boston Pops (First week in May through middle of July)
 Calaveras County Fair and Frog Jumping Jubilee (Third weekend in May) May 21, 2011; May 21, 2016; May 21, 2017; May 21, 2022; May 21, 2023
 Chile Battle of Iquique Day
 Dulcimer Days (Third weekend in May) May 21, 2011; May 21, 2016; May 21, 2017; May 21, 2022; May 21, 2023
 Flores de Mayo (May)Celebrated in: El Salvador, Philippines
 Kingsburg Swedish Festival (Third weekend in May) May 21, 2011; May 21, 2016; May 21, 2017; May 21, 2022; May 21, 2023
 Maifest (Third weekend in May) May 21, 2011; May 21, 2016; May 21, 2017; May 21, 2022; May 21, 2023
 National Family Month (Second Sunday in May through the third Sunday in June)
 Preakness Stakes (Third Saturday in May) May 21, 2011; May 21, 2016; May 21, 2022
 Legal Holidays by Countries| Battle of Iquique Day | Chile |  | Independence Day | Montenegro |  | Whit Monday | Antigua and Barbuda, Austria, Bahamas, Barbados, Denmark, France, Germany, Greece, Grenada, Hungary, Iceland, Republic of Congo |  | Whitsun Monday | Andorra | 
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