Roman Catholic Archdiocese of San Juan de Puerto Rico

Galería Nacional (National Gallery) located in Old San Juan within the historic colonial section of the capital of Puerto Rico, houses the largest collection of Puerto Rican paintings from the eighteenth century to the 1960s. The museum is located in the restored Saint Aquinas monastery of the Dominican Order. The monastery along with the adjoining San José Church is one of the first significant works of architecture on the island. The museum's holdings include many important works by José Campeche, Francisco Oller, Ramón Frade, and Rafael Tufiño. The museum is administered by the Institute of Puerto Rican Culture.

San José Church (Spanish: Iglesia de San José), located in Old San Juan within the historic colonial zone of the capital of Puerto Rico, is one of the first significant works of architecture on the island. The church is one of the earliest surviving examples of 16th-century Spanish Gothic architecture in the Western hemisphere.In 2013 it was added to the National Trust for Historic Preservation's list of 11 Most Endangered Historic Places of 2013.

Plaza del Quinto Centenario (Spanish for 'Square of the Fifth Centenary'), also Plaza del V Centenario, popularly referred to as Plaza del Tótem ('Totem Square'), is a modern square in Old San Juan, Puerto Rico, inaugurated in 1992 to commemorate the 500th anniversary of the European discovery and Spanish conquest of Puerto Rico and the Americas and the first European settlement of San Juan. The square is located between the Ballajá and Mercado neighborhoods of the San Juan Antiguo barrio of San Juan, Puerto Rico. It is located next to the Ballajá Barracks, the Puerto Rican National Gallery and the San José Church, close to El Morro and the San Juan National Historic Site.

The Center for Advanced Studies on Puerto Rico and the Caribbean (Spanish: Centro de Estudios Avanzados de Puerto Rico y El Caribe) is a private institute housed in the former San Ildefonso Conciliar Seminary in Old San Juan, San Juan, Puerto Rico that offers graduate studies in arts and philosophy. It was incorporated on February 28, 1968, by Pablo Casals, Luis Muñoz Marín, Roberto Busó Carrasquillo, and Jaime Benítez. However, it remained inactive and without organization until 1976, when Ricardo Alegría made a request before the Council on Higher Education of Puerto Rico to transform the center into an academic institution. The center is currently accredited by the Middle States Association of Colleges and Schools and it publishes La Revista del Centro de Estudios Avanzados de Puerto Rico y el Caribe.

Museo de las Américas is a multidisciplinary museum in San Juan, Puerto Rico dedicated to the arts, folklore, architecture and broader history of the Americas. Its mission is to offer a synoptic view of the history and culture of the Americas from ancient to contemporary, emphasizing in Puerto Rico and its relationship to the continent, through exhibition programs and cultural activities. Founded in 1992 by Ricardo Enrique Alegría Gallardo, a professor at the Universidad de Puerto Rico and founder of the Institute of Puerto Rican Culture, the museum is dedicated to its role in preserving and perpetuating Puerto Rican arts and culture, both within the territory and abroad. Among its temporary exhibitions, the museum has four permanent exhibitions: The Popular Arts in the Americas, The African Heritage, The Indigenous of America and Conquest and Colonization: Birth and Evolution of the Puerto Rican Nation. Museo de Las Americas is a multidisciplinary, multicultural and multidimensional learning museum, responding to a diverse community, which allows it to consolidate itself as a cutting-edge institution in Puerto Rico. It is currently housed in the former Ballajá Barracks, built between 1854 and 1864 as one of the last major architectural projects of the Spanish colonial rule over the island before it was annexed by the United States in 1898. Initially, when Puerto Rico was annexed by the United States, the federal government paid the Catholic Church for this property, among others in the area. Ownership of the property, claimed by the Catholic Church, was not a straightforward matter and had to be resolved by the Supreme Court. The Government of Puerto Rico acquired the building in 1976 through a transfer from the Government of the United States with the commitment of restoring it and using it for cultural, educative, and touristic purposes. In 1986, a reform plan for the San Juan Historic Zone was sketched and the building was restored from 1990 to 1993.

The Academia Puertorriqueña de la Lengua Española (Spanish for Puerto Rican Academy of the Spanish Language) is an association of academics and experts on the use of the Spanish language in Puerto Rico. It was founded in San Juan on January 28, 1955. It is a member of the Association of Spanish Language Academies. The association works with the Royal Spanish Academy to add new words to the Spanish lexicon. In 2017, the academy was instrumental in adding the word "reguetón" to the official Spanish dictionary.The academy put together a website with Puerto Rican vocabulary which can be searched by themes.

Casa Blanca is a house museum located in Old San Juan within the historic colonial section of the capital of Puerto Rico.

Hotel El Convento is a small hotel in Old San Juan, Puerto Rico, in what was a Carmelite convent, adjoining the San Juan Cathedral square. The cathedral is the second-oldest cathedral in the Western Hemisphere. Hotel El Convento is the oldest member of the Historic Hotels of America. It was also named the premier Small Luxury Hotel in Puerto Rico by the Small Luxury Hotels of the World organization.

Mercado, located within Old San Juan, is one of 7 subbarrios in San Juan Antiguo barrio in the municipality of San Juan in Puerto Rico.

The Institute of Puerto Rican Culture (Spanish: Instituto de Cultura Puertorriqueña), or ICP, for short, is an institution of the Government of Puerto Rico responsible for the establishment of the cultural policies required in order to study, preserve, promote, enrich, and diffuse the cultural values of Puerto Rico. Since October 1992, its headquarters have been located at the site of the old colonial Spanish Welfare House in Old San Juan. The ICP was created by order of Law Number 89, signed June 21, 1955, and it started operating in November of that year. Its first Executive Director was Dr. Ricardo Alegría.

The Catedral Basílica Metropolitana de San Juan Bautista, or in English, Metropolitan Cathedral Basilica of Saint John the Baptist, is the Roman Catholic cathedral of the Archdiocese of San Juan de Puerto Rico. The cathedral is one of the oldest buildings in San Juan, located in Old San Juan, the oldest cathedral in the United States, and is the second oldest cathedral in the Americas. Even though the Cathedral of Santa María la Menor in Santo Domingo in the Dominican Republic, is an older church building, the Cathedral of San Juan Bautista was the first cathedral church in the Americas as San Juan, then known as the city of Puerto Rico, was the first diocese of the New World with bishop Don Alonso Manso in 1511. The site is the location of the first church built in the New World. A private Puerto Rican foundation known as Fundación Protectora de la Catedral Metropolitana de San Juan, Inc. has been established to fund the historical restoration of the building and its art treasures for its 500th anniversary in 2021, and to protect it for coming centuries.

The Pablo Casals Museum (Spanish: Museo Pablo Casals), located on San José Square in Old San Juan, San Juan, Puerto Rico, is a museum dedicated to the Catalan Puerto Rican cellist, composer and conductor Pablo Casals, who lived the last 17 years of his life in San Juan where he composed his masterpiece El Pessebre. In addition to his piano, his cello, historical photographs, some of his musical instruments and personal belongings, the museum also has a media and music library which visitors can browse.