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

Other days

reading

Reading Day
cursing

Cursing Day
fiancee

Fiancee Day
tulip

Tulip Day
hoodie

Hoodie Day
latina equal pay

Latina Equal Pay Day
gum

Gum Day
raise awerness of zeus

Raise Awerness Of Zeus Day
youth

Youth Day
ruby

Ruby Day