Jay Reed, a student from Colorado Springs, also made the trek to Boulder to smoke some weed, chill out and satisfy his munchies with some snacks.

"We're here to just to f**kin' hang out and support this and support this cause," the bandana sporting Reed said motioning to the crowd after sucking smoke from a blue glass pipe.

While Reed's "cause" was not readily apparent, others preached their pro-marijuana messages from the low stone walls that line the quad, waving large green signs with boldly printed legalization slogans.

Kriho said marijuana has a variety of positive uses –– medical, recreational and industrial –– and said the plant has been used by human civilizations without major consequences for thousands of years.

"It's ingrained in international culture. We could all benefit from [its legalization]," she said.

Bell agreed, saying CU's annual 4/20 celebration draws large, peaceful crowds and boasts no dangers. That, he said, shows that marijuana's illegal status is unnecessary.

Plath, who emphasized that she did not inhale the marijuana smoke, also said the celebration was about pushing for legalization.

However, not everyone in attendance smoked marijuana or condoned its use.

Waving a red-lettered sign that read "Getting high makes you stupid" on the edge of the throng, CU-Boulder students Troy Johnson and Garrett Graff said the whole celebration was ridiculous and served only to "create an atom bomb of smoke above campus."

Johnson said numerous people had yelled at them for protesting the smoke-out, and Graff said the event was much less about standing up for marijuana legalization than many partakers tried to pretend.

"I think 90 percent of the people here just want to smoke and get high on a school day," Graff said.

Despite the blatant disregard for controlled substance laws, law enforcement officers said their primary concern was maintaining public safety. No tickets were issued during the gathering.

"No structures, no cars, nothing weird," said one CU police officer who requested anonymity because the department didn't authorize officers to talk to the media. "As you can see, the number's overwhelming."

The heavy police presence did little to deter most of the gathering as they lit up any kind of joint, blunt, pipe or bong they could find and pass around. Some, including Mike, even seemed to take special joy from doing the drug in front of police officers.

"I love it. I think it's awesome," he said. "The cops can't do anything about it."