Basílica del Santísimo Sacramento, Minor basilica in Retiro, Buenos Aires, Argentina

The Basilica of the Most Holy Sacrament stands at San Martín 1039 in Retiro, its light brown and tan stone facade rising in three sections with three deep arched entrances, the wider central one under a dark metal canopy. Two tower-like sections with rows of arched windows end in green tiled domes topped by crosses, and a statue group with a cross sits between them. Inside, three naves in neo-Gothic style hold stained glass, Baveno and Vosges granite, Verona red and Carrara white marble, and five towers rise in all, three at the front and two at the apse.

Mercedes Castellanos de Anchorena commissioned the church, which was built over eight years by the architects Coulomb and Chauvet and supervised by the superior of the Congregation of the Most Holy Sacrament, who chose the materials. The design is eclectic, inspired by Angoulême Cathedral. Sources differ on the consecration year: 1914 or 1916. Anchorena, who lived in the Palacio Anchorena about 150 metres away, is buried in the crypt.

The church is dedicated to perpetual adoration of the Blessed Sacrament, and unlike other basilicas of its era the altar table is not emphasised. It became the favoured venue for weddings of Buenos Aires high society. In the crypt rest the remains of Mercedes Castellanos de Anchorena, who commissioned the building and lived about 150 metres away in the Palacio Anchorena.

The church stands at San Martín 1039 in Retiro, about 150 metres from the Palacio Anchorena. It is an active place of worship, so dress and behaviour should suit a visit during services. The main entrance is the wide central arch under the dark metal canopy; the two side arches lead into the same three-aisle interior.

The organ, built by Mutin-Cavaillé-Coll in 1912 and installed in 1915, has 4,980 pipes in tin, lead, pine and zinc across 73 stops and four manuals. It is the largest organ in South America and the largest Cavaillé-Coll instrument outside France. Charles Mutin attended its 1915 inauguration, where Widor's Fifth Symphony was played.