Slidell / s l aɪ ˈ d ɛ l / is a city on the northeast shore of Lake Pontchartrain in St. Tammany Parish, Louisiana, United States. The population was 28,781 at the 2020 census .  It is part of the New Orleans − Metairie − Kenner metropolitan statistical area .
Covington is a city in, and the parish seat of, St. Tammany Parish, Louisiana, United States. The population was 11,564 at the 2020 United States census .  It is located at a fork of the Bogue Falaya and the Tchefuncte River .