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

Other days

camera

Camera Day
lisp

Lisp Day
cuddle up

Cuddle Up Day
polyamory

Polyamory Day
prosecco

Prosecco Day
comfy

Comfy Day
bow tie

Bow Tie Day
artists

Artists Day
cat girl

Cat Girl Day
blanket fort

Blanket Fort Day