The Buick Lucerne is a full-size upscale sedan sold by Buick from 2006 to 2011. Introduced at the 2005 Chicago Auto Show, the Lucerne replaced both the Park Avenue and the LeSabre for the 2006 model year. Based on a revised G platform (though GM continued to refer to it as the H platform), it served as Buick's flagship until replaced by the second generation Buick LaCrosse. It is named for elegant financial and cultural center Lucerne, Switzerland.