The Root Beer float was invented in 1874 by a Philadelphia soda vendor named Robert McCay Green. As the story goes, Green ran out of ice on a steamy summer day and was forced to improvise. He bought ice cream from a neighboring vendor, mixed it with his root beer, and a new beverage was born.

Since 1874, dozens of variations on have been built on the original concoction, including the Coke float, Boston cooler, and Orange float. Root Beer Floats and other ice cream-soda mashups have generally been most popular among kids and teens, but that didn't stop some mixologist from blending Guinness Stout, chocolate ice cream, and espresso to make a beer float, also know by its way-more-awesome name, the Shakin' Jesse. Plenty of other variations of carbonated beverage-meets-ice cream exist throughout the country - some booze-filled and some not - but none match the fame of the simple, classic Root Beer Float.

It's not known on which day Robert Green first mixed root beer and vanilla ice cream, but that's not important. National Root Beer Float Day is Sunday, August 6, and like National Donut Day and National Hot Dog Day – the holiest of American holidays – free root beer floats can be had.

Deals For National Root Beer Float Day 2017:

• A&W Restaurants: Enjoy a small root beer float with any purchase on 8/6.
• Hy-Vee: Discounts vary by location, such as the Hy-Vee in Silvis, Illinois that is selling root beer floats for $1 on 8/6. Check your local Hy-Vee!
• Peace Tree Taproom: Get $5 root beer floats.
• Red Robin: Get bottomless root beer floats for $4.49
• Saint Arnold Brewery: Have a family-friendly afternoon at the brewery where every root beer float purchase will come with a limited edition souvenir Root Beer cup.
• Wienerschnitzel: Enjoy a free root beer float with any purchase on 8/6.

Cover photo via Flickr/danieldanielkwok.