The christening ceremony took place in the medieval town of Viviers.
It was followed by a celebratory gala dinner and sailing, attended by German-speaking media, tour operators and travel agents.
A separate maiden voyage event and sailing for UK trade and media will take place on Sunday 20 August.
Last year, Seaside Collection entered the luxury river cruise market as Riverside Luxury Cruises, following the acquisition of the Crystal Cruises river fleet.
Riverside Ravel will sail the Rhône between Lyon and Arles, and Riverside Mozart sails on the Danube.
Anouchka Gerlach, Co-Founder, said: “We are delighted that we can now offer our guests the French way of life with the Ravel.”
Riverside Ravel has 55 luxury suites, four restaurants and a fitness centre including swimming pool, gym and spa.
A premium all-inclusive including excursions package costs from £2,327 per person, based on a Melody Suite.
