São Paulo, a megacity of over 12 million people, hides many mysteries beneath the feet of those passing through its streets, despite the frantic hustle and bustle of daily commuters.

Unlike our guide to lookout points for experiencing São Paulo from above, we now present a selection of underground sites that are largely unknown to the general public, each preserving a piece of the city's history. Theaters, an aquarium, an unfinished subway station, and artistic and cultural institutions are among these semi-secret spaces. Explore our selection below:

About thirty years ago, French landscape architect Patrick Blanc became a pioneer in the implementation of vertical gardens in Paris, and later in other cities around the world. Through the creation of vertical structures capable nourishing plant species, these systems allow species to grow on the facades of buildings, considerably reducing a structure's internal temperature and allowing the expansion of green areas to new (vertical) territories within the city.

Blanc's creation was part of a series of developments in understanding what nature adds to the city, recognizing the value of green spaces and their contribution to social, environmental and urban policies. 

There wasn’t much in the way of art that Roberto Burle Marx couldn’t do. He was a painter, print-maker, sculptor, stage designer, jeweler, musician, tapestry-maker and one of the leading landscape architects in the 20th century. Marx’s passion for art, in all forms, strengthened his ability to design landscapes.

The following photo set by Fernando Guerra focuses on Porto's Subway, a project completed in 1996 and projected by the important Portuguese Architect Álvaro Siza Vieira.

Designing a subway station in Porto is about influencing the daily lives of thousands of people, where they daily circulate, establishing flows and routes, in a urbanistic and architectural intervention with large-scale dimensions. Although it demands an extremely functional and austere design, it is possible to see the gestures of the architect through the details and surprises.