Click (or right-click) the search links. Then add a city name and/or year, and search again. Remove or add search terms to find other events, and other cannabis-related images.
Photos, graphics, and image searches. Share link: Image search. Marijuana March:    . Marihuana March:   . Marcha Marihuana (Spanish):    . Marche Mondiale Cannabis (French):   . Marche Mondiale Marijuana (French):   . Marcha Maconha or Marcha Marijuana (Portuguese):      . Google Advanced Image Search. And: Flickr advanced image search. Has "date taken" search too.
See: Flickr advanced image search. For example; here is a search for cannabis set to pull up images taken on May 5, 2018, the first Saturday in May in 2018. The date of the 2018 Global Marijuana March. See Template:GMM yearly city totals. It has dates for each GMM.
Older photos: Archive of Marihemp Network Gallery.
The text inside the expand/collapse box is from here: