The festival season begins in a few days in Montreal. Throughout the summer, we have plenty to keep us busy downtown. Non-stop festivals, mostly outdoors activities, from late June till September. Music from the world, comedy (both in french and english), theater, movies. When one ends, another one starts. The streets are then crowded. Most of the shows are free (except Just For Laugh) ! Famous groups/comedians, happy crowd, laid-back ambiance !
Here are a few links :
Montreal Jazz Festival
Just For Laugh Festival
Les Francofolies
This one is in Quebec City (where I'll be moving next week for a few years - PM me if you're coming to visit)
Quebec City Summer Festival