Oops, it doesn't look like 'crown on different courseafter being a day' is a national day..

Other days

african immigrant and refugee hiv and hep awareness

African Immigrant And Refugee Hiv And Hep Awareness Day
frozen yogurt

Frozen Yogurt Day
me

Me Day
pumpkin

Pumpkin Day
promposal

Promposal Day
bow tie

Bow Tie Day
prosecco

Prosecco Day
nae nae

Nae Nae Day
hiv awareness

Hiv Awareness Day
martini

Martini Day