All buildings eventually die: Sometimes sooner, sometimes later. But artist Calvin Seibert's work lasts no longer than a turn of the Earth. Seibert spends his free time sculpting incredible models on the beach—and they're unlike any sand castles I've ever seen.

Seibert, who goes by Box Builder on Flickr, has been making sand castles since childhood—he only recently started photographing his creations, as he told me today over email. He also uses traditional techniques—though the results are incredibly weird and beautiful.

Here's how Seibert explained his fascination with sand to me:

When I was a kid I made structures that looked like buildings in the early stages of construction. I wasn't interested in finished looking scale models. We lived in a neighborhood where houses were always just being built and I was attracted to that. I thought then that I would be an architect but by high school It became clear that what I had really been making all along were sculptures and so I went to art school and became an artist.

I grew up in Colorado and the sandcastles only got started when I moved to New York and had access to a beach. For many years I never bothered to photograph what I made. Then as I started doing so I also started taking them more seriously. Thinking about how they might evolve. How I push the shapes and ideas.

What's so fascinating, to me, is that each of his models seems to reference a particular period of architecture. Some have the jagged edges and bombastic angles of Soviet Constructivism:

Others look like the heroic cities designed by Italian futurist Antonio Sant'Elia:

Others still hearken back to the sinuous, organic curves of Le Corbusier during the later years of his life:

It's amazing work—and fun whether you care about the architectural history behind these models or not. Check out a few more below, or head over to his Flickr page.

Thanks, Andrew!