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

Other days

camera

Camera Day
lisp

Lisp Day
fiancee

Fiancee Day
lumpy rug

Lumpy Rug Day
hiv awareness

Hiv Awareness Day
lash

Lash Day
singles

Singles Day
believe

Believe Day
stress awareness

Stress Awareness Day
cuddle up

Cuddle Up Day