A 1634 Spanish decree called Havana the “Key to the New World and Rampart of the West Indies.”
Havana’s natural harbor made it a crucial assembly point for Spain’s treasure fleets. Beginning in 1561, ships carrying American silver and other colonial goods gathered there before crossing the Atlantic to Spain, often using the Gulf Stream to speed the voyage. The harbor’s narrow entrance was also defensible, strengthening Havana’s strategic value.
The Spanish phrase was “Llave del Nuevo Mundo y Antemural de las Indias Occidentales.” It was not merely a poetic nickname: the title reflected Havana’s role as both a gateway for imperial commerce and a defensive stronghold protecting Spain’s Caribbean interests. The wording became associated with Havana’s coat of arms.
A common mix-up is Cartagena de Indias, another heavily fortified Spanish Caribbean port with major historical importance. However, the 1634 title in this question belongs specifically to Havana, Cuba. Havana’s defenses later included Castillo del Morro and La Cabaña; Britain captured the city in 1762 during the Seven Years’ War, underscoring its importance.