San Telmo is the oldest barrio of Buenos Aires, Argentina. It is a well-preserved area of the Argentine metropolis and is characterized by its colonial buildings. 

Cafes, tango parlors and antique shops line the cobblestone streets, which are often filled with artists and dancers. A street named the "Illuminated Block" is where many of these important historical buildings can be found.

San Telmo's attractions include old churches (e.g. San Pedro Telmo), museums, food halls and stalls, antique stores and a semi-permanent antique fair (Feria de Antigüedades) in the main public square, Plaza Dorrego. Tango-related activities for both locals and tourists are in the area.

- Wikipedia