BOULDER, Colo. – Protesters demanding that marijuana be legalized marched onto the University of Colorado on Friday, testing the school's determination to push the annual April 20 pot celebration off campus.
The protesters waved signs and a few appeared to be smoking marijuana as they entered the campus. They chanted, "Roll it, smoke it, legalize it."
Only a few dozen marchers crossed onto the university from an adjacent street, but others joined in as they made their way through the campus. By the time the protesters halted on a grassy field near a science building, the crowd appeared to be in the hundreds.
A handful of Boulder city police officers, some in SWAT gear, watched from a corner of the field but made no immediate move on the crowd.
The protesters avoided the Norlin Quadrangle, where last year's rally attracted more than 10,000 people.
The university spread stinky fish fertilizer on the Norlin Quadrangle early Friday and declared it closed, surrounding it with yellow tape and stationing about two dozen officers around the perimeter. That effort appeared largely successful.
Three people were arrested for trespassing when they walked onto the quad, sat down and refused to leave.
"Clearly they wanted to get arrested," campus police spokesman Ryan Huff said.
One of the three protesters, Johnathan Ducombe, told reporters the crackdown is more disruptive than the any of the previous years' rallies.
Huff estimated that the university would spend about $110,000 on law-enforcement Friday, about double the amount spent last year.
At least one other person was ticketed for marijuana possession on campus.
The yellow tape was removed from the quad and officers withdrew shortly after 4:20 p.m., the traditional time for marijuana advocates to light up.
In past years, the April 20 rally at the University of Colorado, which has more than 30,000 students, was one of the largest on any campus in the nation.
Administrators were determined to fend off this year's event and dispel an image in some people's minds that the school was a pot-happy party palace.
Playboy magazine named Colorado the nation's top party school in 2011. The campus also repeatedly ranks among the top schools for marijuana use, according to a "Reefer Madness" list conducted by The Princeton Review.
In addition to closing the Norlin Quadrangle and baiting it with the smelly fertilizer, university officials closed the campus to all unauthorized visitors on Friday and offered a free campus concert by Haitian-born hip-hop star Wyclef Jean timed to coincide with the traditional 4:20 p.m. pot gathering. His contract barred him from making any direct references to marijuana, other drugs or to 4/20.
"We don't consider this a protest. We consider this people smoking pot in the sunshine," said university spokesman Bronson Hilliard. "This is a gathering of people engaging in an illegal activity."
Many students at the University of Colorado and other campuses across the country have long observed 4/20. The counterculture observation is shared by marijuana users from San Francisco's Golden Gate Park to New York's Greenwich Village.
In Austin, Texas, country music legend Willie Nelson, who's open about his marijuana use, was expected to help unveil an 8-foot statue of himself in downtown Austin at 4:20 p.m. local time on Friday. In Southern California, the San Bernardino County Fairgrounds will host "The 420 Festival" with bands and disc jockeys on Saturday.
The number 420 has been associated with marijuana use for decades, though its origins are murky. Its use as code for marijuana spread among California pot users in the 1960s and spread nationwide among followers of the Grateful Dead.
Like most counterculture slang, theories abound on its origin. Some say it was once police code in Southern California to denote marijuana use (probably an urban legend). It was a title number for a 2003 California bill about medical marijuana, an irony fully intended.
Others trace it to a group of California teenagers who would meet at 4:20 p.m. to search for weed (a theory as elusive as the outdoor cannabis crop they were seeking). Yet the code stuck for obvious reasons: Authorities and nosy parents didn't know what it meant.
In Colorado, recent 4/20 observations blossomed alongside the state's medical marijuana industry. Approved by Colorado voters in 2000, medical marijuana boomed after federal authorities signaled in 2009 they would pursue higher-level drug crimes. All marijuana is illegal under federal law, though Colorado voters this November will consider a ballot measure to legalize it for recreational use by adults over 21.
Thousands of people gathered Friday afternoon near the Colorado state capitol in Denver for the start of a two-day marijuana rally, police said.
Officers were ticketing people they saw smoking marijuana if they did not have a medical marijuana card, Detective Raquel Lopez said. Less than a handful of tickets were issued by mid-afternoon, she said.
Seconds before 4:20 p.m., the crowd chanted a countdown, and at zero, a cloud of smoke billowed up over their heads.
A fair-like atmosphere prevailed, with vendors selling munchies from food carts and one person peddling glass pipes from a suitcase.
Others rebelled against the gatherings.
The University of Colorado's student government supported the university's anti-4/20 actions. And other Colorado students created a Facebook campaign urging their colleagues to wear formal clothing to school on Friday to repudiate the party-school reputation.
Associated Press writers Kristen Wyatt, P. Solomon Banda and Thomas Peipert contributed to this report.