Facebook employees for the first time are sitting at their new desks in an entirely new space.

MPK20 has just opened up for business. It's Facebook's new Menlo Park office, a 430,000-square-foot building designed by architect Frank Gehry, whose notable works include the tower at 8 Spruce Street in Lower Manhattan, the Experience Music Project in Seattle, the Guggenheim Museum in Spain, the Walt Disney Concert Hall, the Louis Vuitton Foundation in Paris, and more.

Unlike Apple's spaceship campus and Google's glass canopy design for its headquarters, Facebook's office is one massive room. And that's it. Mark Zuckerberg, Facebook's CEO, has described it as the "largest open floor plan in the world" with a 9-acre rooftop park, 15 floor-to-ceiling art pieces, and a number of other striking visual elements, all of which have been captured and posted to Instagram by Facebook staffers.

We've cherry-picked a collection of Instagrams that show off not only the outside/inside but also all the custom art. You'll notice that the single space also has a lot of smaller spaces that work together, fitting in thousands of people. Zuckerberg said the building is simple and isn’t fancy, but that's the point. Although it's basic, a lot of its inner stuff add depth to the overall design.

If you want to see more photos, check out the the Instagram tags #mpk20firstlook and #mpk20.

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