Regla is one of the 15 municipalities or boroughs in the city of Havana, Cuba. It comprises the town of Regla, located at the bottom of Havana Bay in a former aborigine settlement named Guaicanamar, Loma Modelo in a peninsula dividing Marimelena from Guasabacoa inlets, and the village of Casablanca located at the entry of the Havana Bay.