Every year on April 20 some cannabis enthusiasts around the world engage in collective cannabis smoking and ‘roll one up’ to mark their love for the herb and campaign for the legalisation of cannabis.
The day, stylised as 4/20, is also used by activist groups, such as Crainn here in Ireland, to highlight ongoing issues with the regulation of cannabis and to bring awareness to the large number of people who still face criminal penalties for the consumption of cannabis.
From the origin of the term to what happens on the day, here is everything you need to know about 4/20.