Since its launching in 1999, the hot air balloon in the Parc André Citroën in the 15th arrondissement of Paris has offered one of the best views of the city. The huge, 32-meter (105 ft) balloon (more or less the equivalent of a 12-story building), tethered to the ground, can take up to 30 adults on a sightseeing adventure some 150 meters (492 ft) high in the Paris sky. Since 2008, the balloon has also been giving an instant reading of the air quality over the capital. Using information fed to it from stations scattered throughout the city the balloon’s color changes from a clean green to a highly-polluted red. A separately colored strip at the bottom indicates air quality in traffic.

Parc André Citroën, 15th. Métro: Javel/ Balard. €10 weekdays, €12 weekends. website

Originally published in the April 2008 issue of France Today