Maryland Heights is a second-ring west-northwest suburb of St. Louis, located in St. Louis County, Missouri, United States. The population …Maryland Heights is a second-ring west-northwest suburb of St. Louis, located in St. Louis County, Missouri, United States. The population was 27,472 at the 2010 census. The city was incorporated in 1985. Edwin L. Dirck was appointed the city's first mayor by then County Executive Gene McNary. Mark M. Levin served as City Administrator from August 1985 to 2015.