With 245 years of history and tradition behind it, you'd be forgiven if you didn't know quite everything about America’s Independence Day. From the true story behind the signing of the Declaration of Independence to some staggering hot dog statistics, here are 10 things you might not know about the Fourth of July. Congress hadn’t even begun designating federal holidays until June 28, 1870 [PDF], with the first four being New Year's Day, Independence Day, Thanksgiving, and Christmas. Billed as “America's Oldest Fourth of July Celebration,” the town of Bristol, Rhode Island, has been doing Independence Day right since 1785. There are around 15,000 Independence Day fireworks celebrations every year.