Regla (rāˈglä) [key], municipality (1994 est. pop. 44,000), Ciudad de La Habana prov., W Cuba, a commercial and industrial suburb of Havana. It grew up around the hermitage of Nuestra Señora de Regla (est. 1690) and was officially founded in 1765. During the colonial period, Regla was a smuggling center for Havana.