San Juan Bay in the context of "La Fortaleza"

San Juan Islet (Spanish: Isleta de San Juan) is a 3-square-mile (7.8 km) islet or small island on San Juan Bay in the Atlantic coast of northern Puerto Rico. Home to Old San Juan, it is the site of the oldest permanent European settlement in Puerto Rico (1521), and the second-oldest European settlement in the West Indies after Santo Domingo (1496). Due to its strategic location in the Caribbean during the Spanish colonization of the Americas, it is home to a city wall and a number of militaristic buildings such as El Morro Castle. Today, it is also home to many of Puerto Rico's government buildings such as the territory's capitol building (El Capitolio).

The Walls of Old San Juan (Spanish: Murallas del Viejo San Juan) is a defensive city wall that surrounds the western end of the San Juan Islet, site of the historic district of San Juan, Puerto Rico. This defensive wall system was built between the 16th and 18th centuries to protect the city and the Bay of San Juan, a highly strategic point in the Caribbean. These walls, along with the defensive fortresses in Old San Juan (La Fortaleza, El Morro and San Cristóbal), form part of the UNESCO World Heritage Site-designated San Juan National Historic Site as they are characteristic examples of the historic methods of construction used in military architecture which adapted European designs and techniques to the special conditions of the Caribbean port cities.

San Juan remains the only walled city under the United States jurisdiction, with walled cities like Boston, Charleston and New Orleans no longer having walls after the 18th century, although St. Augustine, Florida, still retains several wall remnants. Examples of other North American walled cities that retain their ramparts are Quebec City in Canada and Campeche in Mexico. The bartizans (garitas) found along the walls are considered emblematic of the city of San Juan and a symbol of historic heritage preservation in Puerto Rico.

Castillo San Felipe del Morro (English: Promontory Castle of Saint Philip), most commonly known as El Morro (The Promontory), is a large fortress and citadel in the Old San Juan historic quarter of San Juan, the capital municipality of Puerto Rico. Commissioned by King Charles I of Spain in 1539, it was first built as a fortified tower in honor of King Philip II, who oversaw its expansion into a hornwork bastion fort by 1595. Over the next 200 years, especially in the reign of King Charles III, El Morro continued to be developed to reach its current form in 1787. Rising 43 metres (140 ft) from the Atlantic shoreline with 5.5 to 7.6 metres (18 to 25 ft) thick walls, the six-leveled edifice stands on a steep, rocky headland promontory on San Juan Islet guarding the entry to San Juan Bay, the harbor of Old San Juan. El Morro, alongside La Fortaleza, San Cristóbal, El Cañuelo, and other forts part of the Walls of Old San Juan, protected strategically and militarily important Puerto Rico, or La Llave de las Indias (The Key to the Indies), from invasion by competing world powers during the Age of Discovery and Sail. It was designated a World Heritage Site by UNESCO in 1983.

La Fortaleza and San Juan National Historic Site in Puerto Rico is a UNESCO World Heritage Site located in Puerto Rico, an unincorporated territory of the United States in the Caribbean. The world heritage site consists of several historic defensive structures built by the Spanish Empire between the 16th and 20th centuries to defend the strategically located colonial city of San Juan and its bay from foreign attacks. These fortifications are among the oldest European-built defensive systems and largest of its kind in the Western Hemisphere. In addition to its historic importance the site is notable for its architectural significance as one of the most prominent military adaptations of Renaissance and Baroque architecture in the Americas.

The Capitol of Puerto Rico (Spanish: Capitolio de Puerto Rico), also known as Casa de las Leyes (House of Laws), and most commonly referred to as El Capitolio (The Capitol), is the seat of the Legislative Assembly of Puerto Rico, a bicameral legislature composed of a Senate and a House of Representatives responsible for the legislative branch of the government in the archipelago and island. Located in San Juan Islet immediately outside the city walls of the Old San Juan historic quarter in the capital municipality of San Juan, the ocean and bayfront, Neoclassical Beaux-Arts style, entirely white marble-cladded edifice was built by architect Rafael Carmoega between 1921 and 1929 to resemble the Pantheon in Rome, using as inspiration the Low Memorial Library in New York City. It was added to the U.S. National Register of Historic Places in 1977.

Situated in the center of San Juan Islet in the Puerta de Tierra historic district overlooking the Atlantic Ocean in the north and San Juan Bay in the south from an elevated point, the Capitol of Puerto Rico is about 1 mile (1.6 km) from both the La Fortaleza, seat of the executive branch, in the Old San Juan historic quarter in the western end of the Islet, and the Supreme Court Building, seat of the judicial branch, in the eastern end of the Islet in Puerta de Tierra. The Court and Capitol are directly connected via Luis Muñoz Rivera Avenue in the north and Juan Ponce de León Avenue in the south, both of which are directly linked to La Fortaleza via San Francisco Street in the north and Fortaleza Street in the south.

Fortín San Juan de la Cruz (English: Fort Saint John of the Cross), most commonly known as El Cañuelo, was built on Isla de Cabras in the Palo Seco barrio of the municipality of Toa Baja, at the western end of the entrance to San Juan Bay, in Puerto Rico. The square coastal fort has massive sandstone walls that date back to the 1630s. Although the U.S. Navy bombarded the fort in 1898, the fort survived. Today the fort is part of the San Juan National Historic Site, which is listed as a UNESCO World Heritage Site and on both the National Register of Historic Places and the Puerto Rico Register of Historic Sites and Zones. The fort is not open to visitors, but it can be viewed from its exterior.

Guaynabo (Spanish pronunciation: [ɡwajˈnaβo], locally [wajˈnaβo]) is a city and municipality on the northeastern coastal plain of Puerto Rico. Located west of the capital San Juan, east of Bayamón, south of Cataño and San Juan Bay, and north of Aguas Buenas, Guaynabo is spread over 9 barrios and the downtown area and administrative center of Guaynabo Pueblo. With a land area of 27.13 square miles (70.3 km) and a population of 89,780 as of the 2020 census, it is part of the San Juan metropolitan area. The studios of WAPA-TV, the most watched television station in Puerto Rico, are located in Guaynabo.