Here’s the number of the day (at least if you’re a fan of burritos): 20.

Chipotle is turning 20 years old, and in honor of that the company is launching a contest to give 20 grand prize winners free burritos for 20 years. The contest will take place over 20 days and will involve a series of 20 online puzzles. Each day that the contest is held, Chipotle will also give 20 lucky participants free burritos for a single year.

Billed as a “three-week-long treasure hunt,” Chipotle is calling it “Adventurrito.” There will be a single puzzle to solve every day, all culminating in a final Grand Prize puzzle on August 1st. In order to even unlock the final puzzle and have a chance to win one of the 20 Grand Prizes, you have to solve all of the previous 19 puzzles by August 1st.

Here’s what Chipotle has to say about the puzzles:

The first 19 puzzles will vary from quick, easy puzzles to more challenging game play, and will incorporate Chipotle history as well as its commitment to better food from more sustainable sources. Each will be accompanied by a video clue presented by high-profile friends of Chipotle, including celebrities, athletes, political leaders, and farmers who are friends with the company.

Puzzle hints in the form of haikus, or “Hai-clues,” will also be available to players who need a little extra help solving the puzzle. Hints can be unlocked by visiting any Chipotle restaurant and texting a unique receipt code (found at the bottom of all Chipotle receipts throughout the duration of the contest) to 30364. From there players will receive a hint code that can be entered at Adventurrito.com to reveal the Hai-clue. Once a puzzle is answered correctly the player will earn a medallion and all 19 medallions must be collected to unlock the final puzzle.

“Twenty years in, we are changing the way people think about and eat fast food,” said Steve Ells, founder, chairman and co-CEO of Chipotle. “That vision has connected with a lot of people and helped to make them very loyal customers. In celebrating this milestone, we thought giving something special to our customers was the right thing to do, since they have given so much to us over the years.”

It’s a pretty complicated promotion – but it’s also a pretty awesome prize. When Chipotle says “free burritos” they mean one per week. So, if you win a grand prize, you really win 1040 free burritos.

You can head on over to Adventurrito.com to sign up. The contest begins in two days, on July 13th.

Eyes on the prize, people: