Downtown Santiago  has the greatest density of sights in the city, clustered in or around the Plaza de Armas , Plaza de la Constitución, Cerro Santa Lucía , Barrio Lastarria , and Barrio Brasil , with a handful elsewhere.
The municipal tourist authority, with separate offices at the Casa Colorada near the Plaza de Armas and on Cerro Santa Lucía , offers free walking tours that include admission to some of the city’s best museums; check for the most current itineraries.
Sights in other comunas tend to be more spread out.
Santiago (population 4,658,687) centers on a triangular colonial core that lies south of the Mapocho, north of the east–west Avenida del Libertador General Bernardo O’Higgins (the “Alameda”), and east of the Vía Norte Sur, the downtown segment of the Carretera Panamericana. Its focus is the rectangular Plaza de Armas.
Santiago Centro consists of several informal but distinctive barrios or neighborhoods. Beyond Santiago Centro, several other comunas have sights and services, most notably the easterly suburbs of Providencia  and Las Condes , and some of these boast their own distinctive neighborhoods.