El Intercambio is a six-foot-wide, 200-foot-long pathway of granite pavers that are engraved with images of life. The largest of these, Portal, references details of the school’s main entryway. In outline, the sculpture of striped Imperial red and Kashmir gold granite recalls Spanish Mission architecture, while cut through it is the profile of a human head. Mind, crafted from the same two types of granite, is the positive head cut out of Portal. It is engraved with a floral pattern, recalling the region’s Hispanic culture; within the design are hidden tools of daily life. On either end of the pathway are Absolute black granite keyholes with windows. The surfaces are engraved with images from science, such as human organs, molecular models, and mathematic equations.