As we get closer to St. Patrick's Day, you might notice drive-thru lines at McDonald's restaurants get longer as more and more people get their springtime treat, the Shamrock Shake. It's a McDonald's institution with a fanantic cult following. Here are 5 facts you might not have known about Shamrock Shakes.

  • 5

    The Shake Had Its Own Mascot, Uncle O'Grimacy

    Remember Uncle O'Grimacy? In the great big universe of McDonaldLand characters, Uncle O'Grimacy has followed the Fry Guys and Birdie The Early Bird into mascot obscurity. Grimace's green uncle was the spokes-blob for Shamrock Shakes in the early 1970s.

  • 4

    They're Not Available Everywhere

    Part of the Shamrock Shake's appeal is its elusiveness. Some cities would have shakes, others wouldn't. Just like the four-leaf clovers that inspired them, you just can't find Shamrock Shakes everywhere. McDonald's said that starting in 2012 shakes would be offered chain-wide. Although online Shamrock spotters still report some shake-less locations.

    Wikipedia/Creative Commons
  • 3

    The Shake Has Its Own Rap

    Two radio DJs in Pittsburgh took their love of all things Shamrock to YouTube creating a Shamrock Shake rap sure to be stuck in your head well past St. Patrick's Day.

  • 2

    The Large Sets You Back 840 Calories

    Oh yeah, this is the part we don't want to think about. Treating yourself to a large Shamrock Shake will cost you 840 calories and 24 grams of fat. If you can mini-splurge with a small you'll take in just 540 calories.

    krynsky/flickr
  • 1

    You Can Make A Close Approximation at Home

    The 'Family Kitchen' blog lists a recipe that combines milk and vanilla ice cream, your standard milkshake building blocks, with peppermint extract and green food coloring. Now you don't need to worry about 'limited time offers' and 'participation may vary.' Make one anytime you want.

    jamieanne/flickr