American Holidays - End 1st July

http://i.imgur.com/kExDyfv.png
I have always wondered about American holidays because, as a British person, we don't celebrate some of the holidays that the American's celebrate. For example, one holiday is coming up which is on the 4th of July and this holiday is known as Independence Day . America also celebrate Thanksgiving, which we don't. It got me to the point of thinking of my own holiday that I could create.

For this competition, I'd like you to make up any sort of holiday and what that day would consist of. Extra brownie points if you tell us the date you would hold this on.

Prize: 10 Credits, 15 Rep and 2 Raffle Tickets