The GAM — Centro Cultural Gabriela Mistral — is Santiago's principal contemporary arts centre, occupying a large brutalist complex on the Alameda opposite Cerro Santa Lucía. The building has an extraordinary political history (see the story above) and its current incarnation as an open, publicly accessible cultural space feels like a deliberate act of reclamation.
The centre has multiple performance spaces (including a 1,500-seat main theatre), a free rooftop terrace with good views toward the Andes, galleries, and public plazas. There are free exhibitions, concerts, and cultural events most weeks, and the programming deliberately mixes highbrow and popular. The café and outdoor terraces are good spots to sit on a sunny day in the middle of the city. Check the website for current programming; the free rooftop access is independent of scheduled events.