Mobile is a city and the county seat of Mobile County, Alabama, United States. The population within the city limits was 187,041 at the 2020 census, down from 195,111 at the 2010 census. It is the fourth-most-populous city in Alabama, after Huntsville, Birmingham, and Montgomery. Considered one of the Gulf Coast's cultural centers, Mobile has several art museums, a symphony orchestra, professional opera, professional ballet company, and a large concentration of historic architecture. Mobile is known for having the oldest organized Carnival or Mardi Gras celebrations in the United States. Alabama's French Creole population celebrated this festival from the first decade of the 18th century. Beginning in 1830, Mobile was host to the first formally organized Carnival mystic society to celebrate with a parade in the United States. (In New Orleans, such a group is called a krewe.)