Colorado's first-ever recreational marijuana sales began on Jan. 1, 2014. And that's amazing. In perhaps the most fitting twist of all, it turns out that exactly 420 days elapsed between Nov. 6, 2012, the date Colorado citizens voted to legalize marijuana with the passage of Amendment 64, and the date of the first sale.

Mind. Blown.

Counting Nov. 7 as day one of the post-prohibition world, here's our math.

The number "420" is significant in pot culture and is celebrated annually on April 20 (4/20) by marijuana enthusiasts around the world; its origin, however, has been debated for decades. The Huffington Post's Ryan Grim wrote a detailed account of the word's roots connected to a group of men known as the "Waldos".