If you're traveling by bus or train, chances are you'll be passing through CECAP. This terminal is an important transportation hub for the area and an attraction in its own right.
You'll be spoiled for sightseeing choice when staying in Guarulhos. CECAP is an ideal place to begin here, but there are numerous other fine attractions to explore. Internacional Shopping Guarulhos, Parque Shopping Maia, and Cantareira State Park are not far from the transportation hub and will fill in your day nicely.