Islands in the Sea
This is the famous rock garden of Ryoan-ji. Although the concept behind this majestic garden is complicated, I think just viewing it is, in it's own way, incredibly satisfying just to digest. Your eyes move over these shapes that you can feel are familiar. These islands in this puddle of pebbles, anyone can understand it's a visual representation of some sort of Chinese or Japanese landscape painting taken into a 3 dimensional space, but then you might be tempted to ask why. Another door opens, and you realize the onion you're chopping into has only sliced the outermost layer.
The garden is actually a form of meditation. Zen buddhists use the raking motion, a mundane task, to stimulate their mind like formal meditation would. It also happens to form an amazing piece of art.