This sign actually gives a good explanation of Biosphere 2; if you would like to see a larger version, click here.

Once upon a time, Columbia University took over Biospehere 2. These were the dorms, now vacant...

Secret second facility, about which the tour guide refused to answer questions.

Secret other buildings, also not discussed.

OK, from the front... this is a damned impressive structure. Though I have to admit that the video about building it really made me thing about watching people put Thunderdome together at Burning Man...

Prettiness in front of the dorms...

"Don't play here, and don't ask questions."

I counted several similar panes of glass, all of which showed evidence of being cracked all the way through. So much for the 100 year structure...

Through this door, the Biosphereans were sealed away.

The front of the rainforest biodome...

Excuses for why a separate power facility was necessary, and did not invalidate the experiment.

Our tour guide claimed to have been a teacher. Something about him said "ex-government agent who normally dresses in black."

OK, an indoor ocean is just cool. All by itself. I want a private coral reef.

Is it just me, or is having an indoor desert in Arizona kinda silly?

And into the basement, where the water is clearly not recycled. Waste products, by the way, are now shipped out of the dome for processing and collection elsewhere. So much for being a closed system...

Inside the lung (one of two), where air could be bled out of the dome to prevent excess pressure when the air got too hot. Or something like that. It sounded like a very cool system, but as with most of the rest of what we were told, I have my suspicions.