Castillo San Felipe del Morro

Castillo San Felipe del Morro (also known as “El Morro”), perhaps the most iconic fortification built by the Spanish in the Americas, covers a 140 foot-high promontory at the entrance to the Bay of San Juan. This fortress consists of 6 levels facing the Atlantic Ocean, all of which were designed to create a devastating artillery fire over enemy ships. By the time of its completion around 1790, it had the reputation of being unconquerable and was the most feared of all the Spanish colonial fortifications.

Construction of the fort began in 1539 on a site chosen for its strategic location at the entrance to one of the best harbors in the Caribbean area. During the late 16th and early 17th century the distinguished Italian military engineers, Bautista Antonelli and Juan Bautista Antonelli transformed El Morro from its original medieval tower shape to a thick-walled masonry stronghold, capable of fully resisting the impact of cannon balls.

The new fort was put to the test during the early stages of its construction. In 1595, the one and only, Sir Francis Drake led an attack against San Juan. Drake had earned a reputation as invincible, and his attack was perceived as a major challenge to the still vulnerable first stages of the Spanish defenses. However, good fortune was on the side of the Spanish. A miscalculation by Drake, together with the bravery of the fort’s defenders led to a totally unexpected defeat for the English. Spain celebrated this victory and perceived it to be a portent of the importance of the fort and the challenge it presented to would-be attackers. Castillo San Felipe del Morro became the gateway to the Spanish empire.

In 1598, George Clifford, Earl of Cumberland, launched a second attack against San Juan. Having learned from Drake’s defeat and recognizing the difficulty of taking on El Morro by sea, Clifford targeted the most vulnerable point of the fort, its land side. His success brought Puerto Rico under English rule for a period of approximately two months. Unfortunately for the English however, according to documentation, dysentery quickly forced the invaders to abandon their prize.

The Dutch were the next to set their sights on taking El Morro. In 1625, the Netherlands were fighting for their independence from Spain and they attacked San Juan as part of that war. However, after 21 days of siege and battle, the invaders were unable to force The Spanish to surrender El Morro to them. Running out of supplies and ammunition, the Dutch decided to abandon the islet, but not without first burning the city down to ashes.
During the late 1700’s, the Spanish crown sent two Irishmen, Field Marshall Alexander O’Reilly and Chief Engineer Colonel Thomas O’Daly to reform the troops and fortifications of Puerto Rico. O’Daly was responsible for the last major construction and renovations at El Morro. Castillo San Felipe del Morro was finished in time to help protect Puerto Rico when the British attacked with considerable resources in 1797.
One hundred years later though, when the Spanish-American War broke out in 1898, the story was completely different. El Morro and entire complex system of defense completed in previous century were outdated. The Industrial Revolution had resulted in advances in technology, weaponry and military tactics that rendered the fort obsolete.
The proud, once impregnable six-leveled fortress was an easy target of the new and powerful naval breech loading artillery the Americans brought to bear. For the first time in over 400 years, enemy fire reached and hit El Morro. The shock of the iconic El Morro being hit by shells and covered with smoke is a visual
The image of the iconic El Morro being struck by shells and covered with a pall of smoke was visual testament that history had taken a turn. The Spanish-American War marked the end of the Spanish presence in the Americas and the beginning of the United Sates as a major world power.
El Morro served as an active U.S. military base during the two World Wars. A bunker, naval observation post and an anti-aircraft gun emplacement were added to the historic fortification. Designed and built to fight wooden sailing ships 400 years earlier, el Morro now watched for potential submarine and air attacks.
It became obvious however, that though Castillo San Felipe had admirably served its purpose for centuries, it was now obsolete. After 1949 when San Juan National Historic Site was established, El Morro became the first section of the fortification system to be operated under the auspices of the National Park Service in Puerto Rico. In 1983, it was designated a World Heritage Site.
Today, it stands as a proud and fascinating monument to the bold aspirations and ingenuity of Western military and cultural tradition. Medieval architecture fuses with early modern and engineering elements of the 18th, 19th and 20th centuries.

Last updated: December 26, 2019

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