Source: Nuclear Secrecy Blog | Alex Wellerstein | May 24, 2013

Overall aerial view of K-25 areaThe K-25 plant at Oak Ridge was the single most expensive part of the Manhattan Project. It was cost about a fourth more than the entire Hanford site. Perhaps unsurprisingly, the building that housed it was pretty big — supposedly the largest single factory in the world under one roof, at the time that it was built.

I had thought about creating some kind of little graphic comparison to show you how big it was — you know, putting it next to The Pentagon and other large buildings —  and then I realized that I wouldn’t really be flexing my geek cred, or taking advantage of a web medium, if I didn’t make a little custom mashup instead. So, I present for you a quick little app that I’m calling, How Big Was K-25?, where you can drag the footprint of K-25 onto anywhere in the world to make a size comparison:

Click here to open the page in its own window.

Click here to read the full post and interesting historical comments