The works that James Harkins designs may not last very long, but they certainly make an impression.
The artist, who is based in New Zealand, installs the pieces on his native beaches by "drawing" them in sand. Their sprawl and subject matter -- staircases, diving boards, boats, docks and mind-bending mazes -- encourage that sunbathers interact with them.
Harkins got the idea for his unconventional canvases from street artists but told ABC News that he sought a bigger, cheaper medium. His proximity to the beach "made it a natural first choice."
Harkins said that friends help him scale the works.
"[They] mark out key points like height and width, while I sit on a hill and give instructions through hand signals," he said.
For Harkins, his chosen medium is an exercise in tonal drawing and the natural beauty of local beaches "beats the stuffiness of a gallery."
Unlike the works that hang in museums, the pieces that Harkins imagines are meant to be touched, walked on, played with, and enlivened by his audiences. Reactions, he said, are "always good."
But he most enjoys hearing from people who insist there only "some sort of magic" could produce his breathtaking works of art.
Harkins calls this piece "Stairway to Heaven."
A man considers this optical illusion.
A woman stands on the threshold of this floating castle.
Once Harkins has completed a work of art, he invites bystanders to interact with his pieces "to make them come to life."
"It takes a bit of organizing to make sure people are looking in the right direction and that their shadows aren't ruining the illusion, but when we get it right the crowd on the beach get[s] a few laughs and enjoy[s] the antics."
An airplane touches down as the tide rolls in.
Volunteers climbed this puzzle of a staircase.
Like many of the installations that Harkins etches, this staircase manipulates perspective to stunning effect.
Harkins said he enjoys crafting "the more geometric shapes." Those are built in "more of an architectural manner, which ... contrasts well with nature."
"Watching the tide take the pieces away never makes me sad," Harkins admitted. But, he added, "the photos I have then become more precious [for] documenting [those three] hours on that day in the sun."