USA/AZ: Biosphere 2

Biosphere 2 was originally built to test and proof the viability of a closed ecosystem to support and maintain human life in outer space. Eight people were sequestered in the the biosphere for two years between 1991 and 1993. The entire system is supposed to provide enough re-usable food and energy to sustain a future outpost on a foreign planet. Sadly, the experiment was not successful back in the 90s and the biosphere hasn’t been used as intended since.