Slightly Stoopid headlined 4/20/2013 at Red Rocks. Photo by Seth A. McConnell, The Denver Post

When did 4/20 Eve become an actual thing? Looking ahead to Slightly Stoopid, Mac Miller, Red Rocks and more

You’ve seen previous 4/20s, Colorado. But can you imagine what 4/20/2014 will look like?

Sure, 2013 was mammoth — from wild concerts and newly legal recreational weed to the big Civic Center smoke-out, which ended abruptly after a shooting injured three people.

Now we have 2014, where recreational pot’s novelty comes from the retail pot shops that will open on Jan. 1. Medical licenses are no longer needed — if you have an ID proving you’re older than 21, you’ll buy your weed at the store and hit the park and the club and your friend’s house and wherever else the revelry takes you.

Fans of Slightly Stoopid and Mac Miller will add Red Rocks to their rounds, as the two acts will headline the foothills venue in Morrison a day early (on April 19) for one of the biggest 4/20 bills the state has ever seen.

Will the plume of smoke in Morrison rival that of downtown Denver’s? There’s something to be said about altitude.

Tickets to the show, $39.95-$75, are already on sale via AXS.