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

Other days

coffee

Coffee Day
cuddle up

Cuddle Up Day
stud

Stud Day
bow tie

Bow Tie Day
slime

Slime Day
artists

Artists Day
self care

Self Care Day
stress awareness

Stress Awareness Day
cursing

Cursing Day
reading

Reading Day