After cutting supplies to El Morro, he successfully acquired a Spanish surrender, but the tropical heat and diseases overwhelmed the British troops and they were forced to retreat and leave the island. There were no significant fortifications between the Boquerón Battery and El Morro, and Clifford was able to march directly to El Morro. Clifford intended to not repeat Drake’s mistakes, and attacked the islet in the east, by the Boquerón Battery and San Antonio Bridge. In 1598 the British attacked again, sending Sir George Clifford to capture San Juan. Not only had Menéndez de Valdés added new fortifications, but a fleet of frigates sitting in San Juan Bay and sunken hulls blocked the entrance of the bay.

Drake was unsuccessful because of some tactical errors, but also the Spanish were well prepared for a British attack. These new additions were put to the test, when in 1595 British privateer Sir Francis Drake attacked San Juan. Menéndez de Valdés added to El Morro, added some of the city’s walls, and created the Boquerón Battery (now Fort San Gerónimo del Boquerón). No further fortifications or general growth occurred in San Juan until 1582 when Captain General Diego Menéndez de Valdés arrived in San Juan to govern the newly upgraded presidio, or military encampment. Poor placement of La Fortaleza and growing fears of British and Dutch privateers instigated the creation of Castillo San Felipe del Morro (El Morro) in 1539. However, its placement is highly critiqued as it provides no protection to the mouth of the port and only protects the new town of San Juan from the south, where the assumption was the attackers were already in the San Juan Bay. After raids by French corsairs along the coast and multiple insurrections against the Spanish by the local Taínos in the following decades, it was decreed that San Juan should be fortified. But it was not until August 1508, when Juan Ponce de León discovered the San Juan Bay, dubbing the area, puerto rico. On November 19, 1493, Puerto Rico was discovered by Europeans, by Italian explorer and colonizer Christopher Columbus on his second voyage westwards.

San juan puerto rico map google