See more… For more yarn bombing photos from around the world, search the hashtag #yarnbombing.

Over the past couple years, perhaps you’ve noticed trees, statues or parking meters occasionally sporting a scarf or sweater. This guerrilla street art is called “yarn bombing,” and Saturday, June 9 marks the 2nd annual International Yarn Bombing Day.

The event, created last year by Canadian yarn bomber Joann Matvichuk, was conceived as a way to unite guerrilla knitters and crocheters the world over.