3月21日，是全年节日最多的一天：

1.世界睡眠日(World Sleep Day)
2.世界森林日(World Forest Day)
3.世界儿歌日(World nursery rhyme day)
4.世界诗歌日(World Poem Day)
5.世界唐氏综合症日(World down syndrome day)
6.消除种族歧视国际日(International Day for the Elimination of Racial Discrimination)