We've seen a lot of 3D street art on HuffPost Culture, but there's something joyful about Leon Keer's fantasy worlds we can't stop looking at.
The Dutch based pop-surrealist has taken his tools and his imagination around the world, transforming unremarkable pavements or walls into glimpses into other universes.
The images look like scenes you could walk or climb right into - not that you always would want to.
Charming: Leon Keer's snake
Many are inspired by computer games and depict small platforms looming over perilous environments, making his work fun to engage with for passing viewers who can hop around and form part of the scene.
In a world bombarded with cleverly edited digital images, there's something reassuring about optical illusions that have been created using little more than acrylic paint, adhesives, solvents and tar.
Check out this collection of our favourites. Which are yours?