As we approach the month of March, that can only mean one thing. The McDonald's Shamrock Shake season is here.

The fast food giant announced the return of its beloved dessert beverage on Feb. 17 on Twitter, which probably made everyone that saw it promptly drop everything and run out to the nearest McDonald's to get their hands on one of these creamy concoctions celebrating St. Patrick's Day.

But what makes the McDonald's Shamrock Shake so great, you ask? I think the more appropriate question is: Is there anything not great about them? The answer is no, because just as Starbucks' Pumpkin Spice Latte is the definitive drink of fall, the McDonald's Shamrock Shake helps usher in spring, even if technically we've still got about a month left of winter and who knows how long of snow. Here are 11 reasons why sipping on a Shamrock Shake should fill all of your pre-spring days, in case you need more convincing.

1. This is What's in it

What makes a Shamrock Shake, exactly? It's quite simple, really. You've got your vanilla ice cream, Shamrock Shake syrup, which gives the drink its green color, whipped cream and a maraschino cherry. Oh, and they are at least 530 calories, so maybe you should go light on those Big Macs.

2. It's Almost 50 Years Old

While gimmicky foods may seem like a 21st century phenomenon, the Shamrock Shake dates back to 1967 when McDonald's franchise owner Hal Rosen first introduced the drink in his Connecticut restaurants in honor of St. Patrick's Day. McDonald's officially picked up the drink in 1970, branching it out into some East Coast and mid-Atlantic locations.

3. It Helped Fund the First Ronald McDonald House

Today, Ronald McDonald House Charities is a famous network of resources created and maintained by the McDonald's Corporation to help seriously ill children and their families. However, this all started back in 1974 when Philadelphia Eagles tight end Fred Hill's 3-year-old daughter was receiving treatment for leukemia. The Hills wanted to help other families going through the same thing, so the Eagles partnered with McDonald's in its Shamrock Shake promotion for that year. For a week, all of the profits raised from the sale of the Shamrock Shake went toward building the first Ronald McDonald House, located in Philadelphia. Who knew Shamrock Shakes could taste this good?

4. Grimace's Uncle Used to Promote Them

Back in the '70s, the uncle of that purple blob-like McDonald's character Grimace, Uncle O'Grimacey, used to appear in commercials for the Shamrock Shake. He was green and had an Irish accent. I don't know about you, but Uncle O'Grimacey doesn't really inspire me to slurp down a Shamrock Shake, so it's a good thing McDonald's retired him.

5. It Wasn't Always Available Everywhere

Once upon a time, Shamrock Shakes were a hot commodity. In addition to already being available during one time of the year, you couldn't find them in every McDonald's restaurant. They were notoriously hard to come by in the New York City area, for instance. It wasn't until 2012 when Shamrock Shakes became available nationwide. Better late than never, I suppose.

6. Yes, You Can Get Them in Ireland

Our neighbors to the north in Canada can snag some Shamrock Shakes too.

7. They're Almost as Popular as the McRib

Because of their limited availability, Shamrock Shakes have inspired almost a cult-like following. McDonald's receives the most inquiries about their availability, right behind the restaurant's other fan favorite, the McRib, according to Yahoo! Food. It's not just a milkshake. It's a way of life.

8. Jimmy Fallon May Have Caused Some Shamrock Shake-related Drama

Back in 2010, New Yorkers were actually able to experience the mint-green goodness of Shamrock Shakes. Or so they thought. Gothamist reported that the same day Jimmy Fallon gave Shamrock Shakes to his entire Late Night audience, an employee at one McDonald's in Union Square said the restaurant had run out of Shamrock Shake syrup because a man had bought 100 shakes. Since Fallon's studio was in a completely different part of Manhattan, it seems unlikely that this would actually have been his fault, but this incident just goes to show you that you do not mess with people's Shamrock Shakes. Ever.

9. Shamrock Sundaes Were Also a Thing

They featured vanilla ice cream and a bright green syrup that looked like Nickelodeon slime. Yum!

10. There Was Once a Giant Shamrock Shake

In celebration of the annual dying of the Chicago River green for St. Patrick's Day, the ad agency Leo Burnett built a ginormous Shamrock Shake that looked like its contents spilled out to color the river green. Unfortunately, you cannot get this size Shamrock Shake at a McDonald's near you.

11. You Can Make Your Own Shamrock Shake

Of course, if you don't live near a McDonald's or are just feeling crafty, you can always make your own take on it. Just Google "Shamrock Shake Recipe," and you'll stumble upon plenty of them, but this one seems particularly straightfoward. You can even add some booze to it if you're of age and want to give it a little kick.

[H/T Gluttoner]

Image: Derek Morrison / Flickr

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