With last week'srelease of floor plans for Apple's proposed Cupertino, Calif., campus reboot, we finally got details on the interior bits of the complex Apple hopes to have finished by 2015. We also have a better idea of how enormous the main building, which will hold some 12,000 employees, will really be.

Over at The Mac Observer, John Martellaro has done the math on the size of the main campus, which up until last week was depicted only in renderings. His findings? The finished building will be ever so slightly larger than the Pentagon.

Using measurements of the Pentagon sourced from Wikipedia, Martellaro figures a circle that could encompass the five-sided building would have a diameter of 1,566 feet. Doing the same circle approach for Apple's proposed campus (which is actually a circular building) yielded 1,615 feet, based on measurements from the scaled drawings and a cross-check with the scaling on Google Maps.

That's neat and all, but how would the two compare if actually stacked on top of one another? Martellaro's got that covered with this "rough" comparison that pits it against the Pentagon, the Empire State Building, and various historical sea vessels:

The Mac Observer

When commenting on Apple's effort--which still needs to go through an environmental impact assessment, development reviews, and public hearings--Cupertino Mayor Gilbert Wong noted the building's resemblance to the Pentagon, while mentioning that this was "not going to be built overnight." The eventual construction of the proposed building, which spans four floors and makes use of two sub-levels for employee parking, is slated for completion in 2015. By comparison, the Pentagon was built in just 419 days.

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