You may spot Petrolina Cathedral from a distance before you actually find this grand building. Rest a while inside if the doors are open or just admire the facade from outside.
If you've got time to stop for a while in Petrolina, Petrolina Cathedral is a great place to start your exploring. This principal church is one of numerous attractions worth seeing here. Fogo Island, Sao Francisco River Park, and Rio Sao Francisco are also waiting to be discovered nearby.