The dense financial and commercial core of Buenos Aires, bounded roughly by Plaza de Mayo to the south, Plaza San Martín to the north, the river to the east, and Avenida 9 de Julio to the west. Most of the grand public buildings from Argentina's early-20th-century peak of prosperity — the Palacio Barolo, the Confitería del Molino, the Teatro Colón — are in or adjacent to the Microcentro.
During the week the streets are crowded with office workers; at weekends the neighbourhood empties. Walking the Avenida de Mayo from Plaza de Mayo to Plaza del Congreso is the best way to see the architecture: Baroque, Art Nouveau, and early modernist buildings jostling along a broad boulevard built to resemble a Parisian grand avenue.