Oops, it doesn't look like 'muzeum day' is a national day..

Other days

law

Law Day
ormille

Ormille Day
slime

Slime Day
tulip

Tulip Day
frozen yogurt

Frozen Yogurt Day
book

Book Day
ride the wind

Ride The Wind Day
fiancee

Fiancee Day
boy friend

Boy Friend Day
boba

Boba Day