• Check the flight status first, since the balloon can close without notice in wind or bad weather, and the official site shows whether it is flying today
• Weekday mornings are quietest, since weekends, school holidays and public holidays bring the longest waits
• No time slot to book: swap an online ticket at the counter on the day, though it does not skip the line

The world's largest tethered balloon rises 150 meters above Parc André Citroën on a steel cable, carrying up to 30 passengers for a flight of about 10 minutes. It runs on helium and an electric winch, so the ride is silent, with a 360-degree view over the Seine and the Eiffel Tower.

Since 2013 it has also worked as a flying lab that measures the city's air pollution.