Not quite everyone knows what 4th of July means to Americans. Though I've met more than one American in Hong Kong who was surprised at first when they found out it isn't a holiday there. I suppose that's conditioning, since we Americans are raised to believe that the entire world either is or desperately longs to be American.
Since no one has listed American holidays, I thought I'd take a crack at it. I wasn't entirely sure what would make the calendar Sara, so I listed a whole bunch and you can pick what counts. There are a lot more than I listed, but I was geting bored, so skipped some less important ones.
Here's a few more:
Mardi Gras – date based on Easter – Carnival – Starts the penitential season of Lent