If you travel by plane:
At Sá Carneiro Airport, take the metro (Line E) and get off at 'Trindade' Station. Then take a new subway (Line D) and get off at 'São Bento' station. From there, walk down Rua Mouzinho da Silveira to Largo de São Domingos, turning later in Rua Ferreira Borges.
If you travel by car (GPS):
41.142208; -8.615416