The Teatro Colón (Colón Theatre) in Buenos Aires is one of the most important opera houses in the world. Its rich and prestigious history and its exceptional acoustics and architectural features rank it among theatres such as Teatro alla Scala in Milan, the Paris Opera House, the Vienna State Opera, the Royal Opera House in London, and the Metropolitan Opera House in New York. The Colón operated in its first venue from 1857 until 1888, after which the building was closed for the construction of a new house. The new improved house opened on May 25th 1908 with a performance of Aïda. In the beginning, the theatre recruited opera companies from other countries, but as of 1925 it has had its own permanent companies (orchestra, ballet and choir) and its own production workshops, which have allowed the theatre to organise its own seasons since the 1930s, funded by the city budget. Since then, the Colón renewed its repertoire annually or by stagione, and has been able to set up whole productions on its own because of the professionalism of its specialised stagecraft staff. Throughout the history of the theatre, no artist of importance of the 20th century has failed to appear on its stage. It's enough to mention singers such as Enrico Caruso, Claudia Muzio, Maria Callas, Régine Crespin, Birgit Nilsson, Plácido Domingo and Luciano Pavarotti, dancers such as Vaslav Nijinski, Margot Fonteyn, Maia Plisetskaia, Rudolf Nureyev, Mijail Barishnikov, and conductors such as Arturo Toscanini, Herbert von Karajan, Héctor Panizza, Ferdinand Leitner, among dozens of others. It is also common for composers to come to the theatre to conduct or supervise the first performances of their productions, a tradition established by Richard Strauss, Camille Saint-Saëns, Pietro Mascagni and Ottorino Respighi.

Located in La boca, the Caminito (little path, in Spanish) is a street museum of colourful painted houses typical of the immigrant dwellings that came to chracterise this portside area towards the end of the 19th and start of the 20th century. The Caminito followed the route of an old stream that once flowed into the Riachuelo, and later, after the river dried up, formed part of a railroad route. After the closure of the railroad, the street was largely abandoned until in the 1950s a group of neighbours decided to regenerate the area and local artist Benito Quinquela Martín began using the tenements as his canvas. Today, there are several works by Argentine artists incorporated as part of the street museum and the Caminito has become a favourite with visitors to the city. Several restaurants offer tango and folk dance shows and street fills with artists offering original crafts and paintings.

Facing the Plaza de Mayo, the Metropolitan Cathedral is the Catholic Church's main site in Argentina, and is where Pope Francis, as Archbishop Jorge Bergoglio, used to perform mass before assuming office in the Vatican in 2013. In Bergoglio's honour, the Cathedral now houses the Pope Francis Museum, which exhibits some of his personal and liturgical objects. The Cathedral’s history is a long and turbulent one. Since the first chapel on the same site was constructed in 1593 under the orders of the city’s founder Juan de Garay, the building has been redesigned and rebuilt seven times. The last construction, the one that we see today, was started in 1752 but not completed until the mid-nineteenth century. You may be struck by the building’s façade, more reminiscent of a Greek temple perhaps than a Catholic church. The twelve Neo-Classical columns at the front represent the twelve apostles of Christ, supporting a triangular frontispiece. This frontispiece, in bas-relief, depicts the encounter between Jacob and his son, Joseph, in Egypt, and was intended as an allegory of the unity of the Argentine nation after civil unrest.

The name of the square commemorates the Revolution of May 25, 1810 , the date on which the citizens gathered there to expel the Viceroy and form a Creole government.