http://worldcannabisweek.com/ – Currently sold out but there is a chance of tickets becoming available.
http://sweetwater420fest.com/- Step out of the sun and into The SweetWater Experience, where you will be able to taste your way through more than 20 unique styles of beers, all from the brewers at SweetWater. Of course we’ll have all of our year-round offerings, plus the freshest Catch and Release seasonal brew; but here’s where it gets fun! We are digging deep in the cellar, and creating a plethora of new beauties that will only be available in this tent at the 420 Festival.
http://www.washingtonpost.com/local/dc-politics/zukerberg-will-host-4-20-day-rally-on-mall/2013/04/10/b23048aa-a1ef-11e2-9c03-6952ff305f35_story.html – If you’re in D.C and feeling political!