On a 2005 Antarctica trip, I also spent some time in Santiago, Chile. Cerro San Cristobel is a mountainous outcropping rising from Barrio Bellavista. The huge Parque Metropolitano at the top features great views of Santiago (unless the smog gets in the way), a 72-foot sculpture of the Virgin Mary, and lots of trails through this natural setting in the middle of the city.

Mark Wasson, http://www.markwasson.com > Trips has detailed summaries of my trips