International de montgolfières de Saint-Jean-sur-Richelieu

Saint-Jean is the largest balloon gathering in Canada and the only festival we track that answers both of a visitor's money questions in public: what it costs to get in, and what it costs to go up. Everywhere else one of the two is missing and usually both. The calendar shows how unusual that is.

That transparency is not a courtesy, it is a consequence of how the event is built. The flights are the festival's own rather than a concession sold to an operator, so the price sits on the same page as the ticket, and the morning and evening windows are priced differently because they are worth different amounts.

It began in the middle of the 1980s, when two balloonists from Montreal noticed that the air over this stretch of the Richelieu valley behaved unusually well and the local chamber of commerce was looking for a reason to bring visitors in summer. The first edition ran with a fraction of today's crews and drew a crowd that surprised everyone involved.

It is now as much a music festival as a balloon one. A concert programme runs every evening under the same ticket, which is how an event of this length pays for itself, and it is also why the crowd on a Saturday night has not necessarily come to see a balloon.

Practically, the flying windows are dawn and early evening, the evening one is the one that sells out, and the whole thing is close enough to Montreal to do without moving hotels. Ten days is long enough that a cancelled morning is an inconvenience rather than a wasted trip.

Ten days is the other thing that sets it apart. Almost every festival on this list runs over a long weekend and lives or dies on the weather it gets; over ten days the weather averages out, and the event can promise a crowd something on days when nothing flies. It is also why the programme has grown a second half that has nothing to do with balloons.