Representatives of other religious communities also took part in the initiative.
The tour will include several stops, including Brussels, Nice and Berlin, where organizers say they hope to meet Chancellor Angela Merkel.
They are expected to conclude the tour and return to Paris on July 14, on the first anniversary of the Nice attack.
The Daesh terrorist group claimed responsibility for the Nice truck attack, which killed 86 people, who were watching a fireworks display on Bastille Day, on July 14, 2016. Daesh also claimed another truck attack on a crowded market in Berlin, which left at least 12 people dead in December last year.
The current tour was initiated by the Imam of Drancy and French writer Marek Halter. They said the tour aimed to send a message of "No" to hate and terror to both Muslim and non-Muslim communities.
"We are here to say that our religion and the values of Islam are opposed to those [of] assassins," Hassen Chalghoumi, the imam of Drancy, said on Saturday.
Some 30 people went aboard the bus on Saturday. More people are expected to participate in the initiative on the way, bringing the total number to 60.
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