San Telmo is the oldest barrio (neighborhood) 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 (adoquines) streets, which are often filled with artists and dancers. San Telmo's attractions include old churches (e.g. San Pedro Telmo), museums, antique stores and a semi-permanent antique fair in the main public square, Plaza Dorrego.