The first thing I notice about doing yoga stoned is my pulse. That otherwise inconspicuous sign of life is suddenly very much present, from my forehead to my pelvis, and the latter makes me want to giggle. I think it's okay to giggle, and so I do. Here inside this garage-turned-yoga studio in central Denver, everyone around me is making noises—giggles and more—upon taking her turn hitting the communal vape that's being passed around.

San Rafael High School’s claims to fame include adult actress Nikki Tyler and Night Ranger’s “Sister Christian” video, but the California campus is best known as the alleged birthplace of 420. Back in 1971, five classmates sought a hidden cannabis crop in the Point Reyes Peninsula, and 420 served as the code word for the search and their 4:20 p.m. meeting time. The legend may or may not be historically accurate, but 420 is definitely the preeminent counterculture holiday with annual cannabis celebrations on April 20. On the fifty shades of green scale, 420 ranks up there with St. Patty’s and Earth Day, and travelers can celebrate with cities to visit, things to do and places to munch.

Punta del Este, Uruguay

It's Saturday morning at an "entrepreneurship retreat" at a hotel in Aurora, Colorado, just outside Denver - well, that's what the sign in the lobby reads anyway.

The word "marijuana" is conspicuously absent from the marquee.

Social media is abuzz over 4/20, the unofficial holiday celebrating all things marijuana, including its consumption. As pot fans across the country commemorate National Weed Day, restaurants in states such as California and Colorado and even in the nation’s capital are promoting 4/20 specials and deals in hopes of luring hungry smokers with cheaper eats. Some dispensaries in those states and others with legal weed are offering discounts or even freebies to certain customers.

Nashvillian Scott Denholm is executive director of Metrc, a tech business that tracks every cannabis plant in Colorado from seed to sale. With more states considering legalization, the growth opportunities are vast.

For years, Nashvillian Scott Denholm has tracked the travel and sale of fruits and vegetables, packages of pharmaceuticals, even the parts of race cars. Now he is focused on tracking a plant that has captured the attention of millions of Americans: cannabis.

DENVER (TheBlaze/AP) — Denver police said there were no major problems as marijuana celebrations continued for a second day on Sunday, but police tweeted a reminder that while recreational use of marijuana is legal in Colorado, people still can’t use it in public.

We’d prefer not to be buzzkills this 4/20 weekend. #ConsumeResponsibly, and designate a sober driver now. #Denver

— Denver Police Dept. (@DenverPolice) April 19, 2015

Everyone brought their best to the 2015 HIGH TIMES U.S. Cannabis Cup in Denver presented by MMJ America, Keef Cola and HighThere! The competition was fierce across all of the categories represented, but ultimately the judges voted for these fine entries. Here's the complete list of winners:

BEST COLORADO SATIVA FLOWER

1st Place - Ghost Train Haze - Greenman Cannabis

While sampling was rampant on the Cannabis Cup’s first day, you may be better off bringing your own. Out-of-state companies, along with Colorado businesses that don’t hold state licenses, were running low on samples by the end of Saturday after being swamped with visitors as the only outlets for free or paid samples.

Yes, paid.

It was only a matter of time before weed got the high-class treatment.

Cultivating Spirits, a Silverthorne tour outfit for foodies with cannabis lovers, is hosting a meet and greet brunch with the Denver-based electronic group Collie Buddz on the morning of April 20.

Held at the cannabis-friendly coworking space Green Labs in Denver, the event features a three-course meal that pairs crepes with — what else? — cannabis. Cultivating Spirits owner Philip Wolf crafted the menu from scratch to highlight the finer side of cannabis.