The tango reflects the cultural brotherhood between Montevideo and Buenos Aires. This was expressed in a joint request submitted by both countries at the UNESCO to declare the tango Intangible Heritage of Humanity, which was granted in 2009. In the last decades of the 19th century, a massive flow of immigrants, mostly Europeans, started to arrive in Uruguay and Argentina. This multicultural melting was increased by the promotion of public education. Tango was born of this mixture. Its musical background is African, Latin-American and European, merged in such a way that the resulting product is completely new. Its origin is fully urban and suburban (arrabalero). Tango lyrics make use of the slang known as lunfardo, born in brothels, jails and taverns of the suburban areas where the working class lived. This feeling of belonging to the suburbs gave rise in Montevideo to neighborhoods with their own tango identity, such the Barrio Sur, the Aduana, the Aguada, and the disappeared Bajo Montevideano.
In Montevideo, tourists can take tango or bandoneón lessons, visit old cafes or enjoy milongas every night of the week. In the traditional Feria de Tristán Narvaja they may find tango antiquities such as tango vinyl records, music sheets, photos and books. In 1917, a song written by Gerardo Mattos Rodriguez, a Uruguayan composer born in Montevideo, was performed for the first time in the intersection of 18 de Julio Ave. and Andes St. This song, called The Cumparsita, is the most famous and recognizable tango of all time.