Oops, it doesn't look like 'Museums Shut For Second Museums Are Shut For A Second day' is a national day..

Other days

Ask Out Your Crush Day

Raise Awerness Of Zeus Day

Cursing Day

China Day

Gum Day

One Day

Embarrass Your Best Friend Day

African Immigrant And Refugee Hiv And Hep Awareness Day

Donate Your Hair Day

Lumpy Rug Day