What is 420 and how did ‘weed day’ get its name?

This might not be the only day you smell cannabis in London’s Hyde Park, but 420 is the only time you’ll see thousands smoking together.

Also known as ‘weed day’, 420 is the unofficial holiday of marijuana – almost a St Patrick’s Day for stoners.

Every year around the world, people gather in public and in private to share a joint.

For some it’s a protest, for some it’s connection, and some just want to get high. Either way it’s controversial.

What is 420 day?

Every year on the 20th day of the 4th month – April 20, in other words – stoners celebrate the cannabis herb.

That often involves sparking up a joint in a park with other aficionados in defiance of laws banning it.

While some countries have legalised recreational or medicinal weed, and others have decriminalised it, in most of the world it’s still a crime.

Cannabis is only legally available in the UK with a prescription from a specialist doctor.

Many participating in 420 today would like to change that.

What does 420 mean? The origin of 420

From Easter Sunday to 420, no ritual would be complete without mystery behind it.

While the international day of consuming cannabis is a relatively new creation, it’s one shrouded in myth and legend – and a few clouds of smoke.

Some say it’s police code for marijuana possession (it’s actually the code for murder).

Others credit Bob Dylan’s refrain of ‘Everybody must get stoned’ in his 1966 song Rainy Day Women #12 & 35, because – bear with us – 12 multiplied by 35 equals 420.

But that leap of logic might just be ‘stoner math’. The most widely accepted origin story instead takes place at a school, long after math class was over.

In 1971, five students would meet by a wall near a statue at San Rafael High School, California, to smoke marijuana at 4.20pm when the bell had rung and extracurricular activities were done.

For them ‘420’ would be their code for cannabis. The term would pop up 19 years later on flyers inviting people to smoke ‘420’ on April 20, at 4.20pm.

Those flyers were handed out in Oakland by fans of Deadhead, whose guitarist had hired Dave Reddix, one of the original San Rafael five.

Once those flyers published in the High Times magazine, the rest was history.

Is anything happening in Hyde Park in 2025 for 420?

If grass and trees could get high, Hyde Park would be blazed at least once a day every year.

Since 1968, 420 has been celebrated annually there. This year is no different, with the Royal Parks anticipating ‘that thousands of people will turn up to take part’ in the unauthorised event.

Organisers invited attendees to join from 11am to 5pm on Sunday for what it called a protest.

Writing on social media, they said: ‘We’re sparking conversations about cannabis laws, advocating for medical marijuana access in the UK, and maybe even ruffling a few feathers with the fuzz.’

Police warned: ‘Using cannabis and other recreational drugs is illegal. Officers will intervene and use enforcement options where proportionate and necessary.’

Six people were arrested last year – two more than the year before.

Around 11,000 people usually attend.

What other 420 events are happening in the UK?

420 isn’t exclusive to London. You can also catch a whiff in East Brighton Park from 2pm to 6pm, or in Bristol’s Castle Park from midday.

There Hemp Garden’s were Durham’s place to be from 12pm to 5pm. In Manchester it was Platt Fields and Hulme Park, while in Leeds it was Woodhouse Moor.

In what countries is weed legal?

While medicinal cannabis was made legal in the UK in 2018, it is still illegal to use it recreationally.

You could face up to 14 years in prison, an unlimited fine – or both – if you are caught growing marijuana here. Possession carries up to five years in prison.

Where in the world is weed legal?

Find out where weed is legal worldwide below:

Recreational use fully legal

The following countries allow you to possess weed for personal use.

• Australia (only legal in Australian Capital Territory)
• Canada
• Germany
• Luxembourg
• Malta
• Mexico
• South Africa
• Thailand
• United States (legal in 24 states plus D.C.)
• Uruguay (legal, but not for foreigners)

The following 24 US states have legalised, or are legalising, Marijuana for personal use:

• Arizona 
• California 
• Colorado 
• Connecticut 
• Illinois 
• Maine 
• Massachusetts 
• Michigan 
• Missouri
• Montana 
• Nevada 
• New Jersey 
• New Mexico 
• New York 
• Nevada
• Oregon
• Rhode Island 
• Vermont 
• Virginia 
• Washington
• Washington D.C. (not a state)

Plus:

• Northern Mariana Islands
• Guam

Medical prescription-only

• Albania
• Argentina (recreational use also decriminalised, but purchase illegal)
• Australia (at federal level and all states)
• Austria
• Barbados (also legal for spiritual use by registered Rastafarians)
• Belgium (recreational use also decriminalised for up to 3g)
• Bermuda (recreational use also decriminalised)
• Brazil (only for terminally ill patients or those who have no other treatment options)
• Chile (recreational use also decriminalised)
• Colombia (recreational use also decriminalised)
• Costa Rica
• Croatia (recreational use also decriminalised)
• Cyprus
• Czech Republic (recreational use also decriminalised)
• Denmark
• Ecuador
• Estonia
• Finland
• Georgia
• Ghana (only for less than 0.3% THC)
• Greece
• Ireland
• Israel (recreational use also decriminalised)
• Italy (recreational use also decriminalised)
• Jamaica (recreational use also decriminalised)
• South Korea (access limited)
• Lebanon
• Lithuania
• Luxembourg (recreational use also decriminalised)
• Malawi
• Malta (recreational use also decriminalised)
• Netherlands (recreational consumption allowed in licensed coffee shops)
• New Zealand
• North Macedonia
• Norway
• Panama
• Peru (recreational use also decriminalised)
• Poland
• Portugal (recreational use also decriminalised)
• Rwanda
• Saint Vincent and the Grenadines (recreational use also decriminalised)
• San Marino
• Slovenia (recreational use also decriminalised)
• Spain (limited)
• Sri Lanka
• Sweden
• Switzerland
• Turkey (Cannabis-derived pharmaceuticals only)
• Ukraine (limited)
• United Kingdom
• Vanuatu
• Zambia
• Zimbabwe

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