I had had no idea! Then I arrived and was overwhelmed. Being in Avignon during the Festival is like living in a circus big top. First, there are street performers everywhere. Then the performers from the 100s of shows advertise their show by dressing in costume and performing or parading through town giving out leaflets. You can not sit quietly and drink a coffee - performers will stop to talk with you constantly and you'll accumulate a small mountain of leaflets (even when you explain that your French is not up to a performance of poetry in French, they'll still leave you a leaflet). Roads are closed for planned and impromptu events. There are performances in English, there are performances in mime, there are dance performances, but the majority of the performances are in French. It isn't to everyone's taste (my travelling companions hated it) but I loved the craziness of the entire time and wanted to stay longer to see more shows. Think Fringe festival on steroids and you'll get the idea.
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