A large police presence has been deployed at Flagstaff Gardens in Melbourne, where pro-cannabis activists are rallying on April 20.

The event, which has attracted hundreds of participants in previous years, calls for the legalisation of cannabis.

In anticipation of the gathering, police set up a makeshift station just 200 meters from the protest site.

#BREAKING: Officers construct makeshift Police Station in Flagstaff gardens ahead of planned 420 rally calling to legalise marijuana.

More to come at https://t.co/EaIX3z3y0M pic.twitter.com/dDVKf7EC8t

— Avi Yemini (@OzraeliAvi) April 20, 2023

The rally is held on April 20, a date known as 4/20, which is synonymous with cannabis culture.

Prior to the event, protesters were cautioned that authorities would likely be monitoring the gathering "as a precaution."

Organisers of the protest say attendees will be "lighting up" and have expressed their discontent with the ongoing prohibition of cannabis and the harsh enforcement by Victoria Police, who they claim waste millions of dollars every year persecuting thousands of Victorians for using cannabis.

They believe that the individuals targeted by law enforcement do no harm and that it's time to end this injustice.

For over a decade, organisers say the annual protest has "aimed to bring together a community of happy, smiling people who deserve the right to live their lives without discrimination and the constant threat of arrest".

By joining communities around the world on April 20, they hope to raise awareness and call for an end to cannabis prohibition in Victoria.

The rally, dubbed "a protest of smiles," will feature talented artists sharing their voices with the crowd.