CKAC is a French-language radio station located in Montreal, Quebec, Canada. Owned by Cogeco, the station operates as a commercial traffic information service branded as Radio Circulation 730. Its studios are located at Place Bonaventure in Downtown Montreal, and its transmitter is located in Saint-Joseph-du-Lac.
CKAC was officially launched on October 2, 1922, under the ownership of the local newspaper La Presse, as the first ever Francophone radio station in North America. CKAC had historically been a dominant station in its early years, with its listenership fuelled by popular programming such as a Sunday church broadcast, news coverage, as well as its broadcast rights to the Montreal Expos of Major League Baseball. In 1968, the station and La Presse was acquired by the Power Corporation of Canada, and CKAC was in turn sold to Telemedia the following year, becoming the flagship of a provincial network of stations.
By the 1990s, the station had begun to lose its dominance due to competing stations and other factors, resulting in a decision by Telemedia to merge its radio network with competing chain Radiomutuel as Radiomédia, and CKAC becoming a joint venture of the two owners. Radiomutuel's CJMS was shut down, and much of its programming and personalities were moved to CKAC. In 2001, Radiomutuel's successor, Astral Media, announced its intent to acquire the remainder of the Radiomédia network and CKAC. However, the acquisition was blocked by the Competition Bureau, resulting in the stations instead being sold in 2004 to Corus Entertainment as part of a larger exchange of assets between the two companies. CKAC became the flagship and provider of talk radio programming to the Corus Québec network, but its newsroom was later shut down in favor of that of its new sister station CINF (later CHMP-FM). In 2007, the station flipped to an all-sports format.
In 2010, Corus sold all of its Quebec radio stations to Cogeco. The following September, CKAC dropped its sports format and switched to traffic information programming, broadcasting live traffic reports for the Montreal area throughout the day.