De Soto came to Havana in the fashion of leisure of the times, and in pursuit of his royal master’s instructions, laid the foundations of a fortress. This work was finished under the direction of his lieutenant while he, himself, was searching an El Dorado in Florida and was finding a miserable death by fever on the Mississippi. The structure which de Soto left as his legacy to Havana is the Castillo de la Fuerza, half hidden, to-day, between the Senate and old post-office building on the Plaza de Armes. La Fuerza has been credited with being the oldest inhabitable and inhabited structure in the Western Hemisphere and the claim is not easily disputed. As early as 1544 a royal decree had been given forth that all vessels entering Havana harbor should salute the little fortress with a ceremony not enjoyed by any other city in the New World save Santo Domingo. The form of la Fuerza is that of a quadrilateral, having a bastion at each of the four corners. The walls are twenty-five feet in height and are double. There is a moat which has not contained water for many years, and arrangements for a draw-bridge which has been replaced by a permanent plank walk. To the seaward is a watch-tower similar in design to that on the fort at St. Augustine, and in this tower is a bell which, tradition says, was rung wildly whenever in the old days a suspicious sail came into the view of the watchman. The little bronze image in the top of the tower is known as “La Habana.” When de Soto sailed out from Havana harbor on that storied expedition through the American wilds which was to end in his death, he left la Fuerza, and with it his command as governor, in charge of his bride, Isabel de Bobadilla. For four years Lady Isabel waited for her lord’s return, spending anxious hours in the little watch-tower of the fort. Only when the tattered remnants of that splendid army which had accompanied the adventurer were brought back to Havana was her long suspense ended. [Illustration: MORRO CASTLE, HAVANA, CUBA] The cellars of la Fuerza contain damp dungeons used as receptacles for modern rifles and ammunition, this part of the old fort being given over to the purposes of an armory. In 1554 Havana was again attacked by the French and partially destroyed and in the following year it fell a victim to pirates. During the wars which marked the reigns of the Emperor Charles V, of Spain, and his son, Philip II, the colony became more and more the object of attack by Spain’s enemies, and in 1585, Havana having been seriously menaced by Sir Francis Drake, it was determined to build additional defences for the city. In 1589 Morro Castle, the Castle of the Three Kings and the Bateria de la Punta were begun; by 1597 they were completed.