Some popular fast food places celebrating National French Fry Day with free fries

FRESNO, Calif. (KFSN) -- The exact origin of the not-so-healthy snack isn't clear. The earliest known reference to 'French fried potatoes' occurs in the English work "Cookery for Maids of All Work" published in 1856.

Some believe the term 'French fries' came, not from France, but from Belgium during the First World War after American soldiers tried the delicacy in the then-French speaking country.

So whether you like them shoestring, curly, or waffle-- grab some ketchup and celebrate National French Fry Day!

Some popular fast food restaurants are offering free deals.

McDonald's-- Order via the French Fry King's App and get a free medium fries not only on French Fry Day, but every day through Sept. 7.

Burger King-- No free fries here this year, but for just $3.49 you can get two cheeseburgers, a small drink and, well, you guessed it, a small order of fries.

Arby's-- Want free curly fries? Just order a Brown Sugar Bacon Sandwich and Arby's will throw 'em in gratis. You'll also get a drink.

Dairy Queen-- A small order of fries will run you just $1 on the 13th at select locations.

Wienerschnitzel-- Through the end of the month, you can get $1 off chili-cheese fries at the chain. Be sure to download the coupon first.