North of Avenue Diagonal, the urban structure of Barcelona gradually changes. The famous octagonal blocks of the Exiample, a monument to the stunning economic, urban and cultural expansion of 19th-century Barcelona, give way to a denser and less regular morphology of former suburban neighborhoods. Somewhat to the west of the connection of the elegant shopping street Passeig de Gràcia and Avenue Diagonal begins Via Augusta, a major arterial street that divides the upper-class neighborhood of Sant Gervasi – Galanyi and the vibrant Vila de Gràcia. The southern part of Via Augusta represents a typical cross-section of a Barcelona avenue: beautifully lined with trees, it gradually climbs towards the elongated Plaça de Gal·la Placídia. That bustling urban space is a major infrastructure junction with an underground station, and according to its physiognomy, rather an expansion of the avenue than a typical square.