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

Other days

ormille

Ormille Day
boyfriend

Boyfriend Day
ask out your crush

Ask Out Your Crush Day
bounce

Bounce Day
boba

Boba Day
fiancee

Fiancee Day
kale

Kale Day
gum

Gum Day
latina equal pay

Latina Equal Pay Day
cursing

Cursing Day