Ballon Generali

The Ballon Generali is a tethered helium balloon rising from the center of Parc Andre Citroen. Its massive, translucent sphere shifts color depending on the air quality, glowing green when the atmosphere is clean and turning red on days with high pollution. Aerophile engineers built it to monitor urban air levels, but locals treat it as a vertical observatory. In nineteen ninety-nine, the balloon became the first of its kind to carry passengers, lifting them five hundred feet above the city streets.