You can get there by subway, but you should not miss the walk when crossing the upper deck of the Luiz I bridge. So, you get to the “other side”, assuming you started at Ribeira towards Vila Nova de Gaia, and face front the Morro Garden. Then you just find the perfect spot, sit and enjoy the view.
If you are a morning person, be sure to go there for the sun rise. Its believed to be the prettiest of the city.
Avenida da República, Vila Nova de Gaia