Cerro Santa Lucía is a small hill in the heart of the city that Benjamín Vicuña Mackenna, Santiago's great 19th-century mayor, transformed into an extraordinary ornamental park in the 1870s. The terraces, stairways, and Moorish-inspired towers carved into and out of the rock are among the most idiosyncratic pieces of public architecture in South America, and the views from the top — close-up over the city's rooftops — are excellent.
The park is free to enter and open during daylight hours. The main entrance is on Avenida Alameda at the western end; the gates closest to Lastarria are also good starting points. The walk to the top takes about 15 minutes. The Terraza Vicuña Mackenna near the summit has a small formal garden and benches. The park closes at night but during the day is one of the city's best urban green spaces, popular with students and office workers.