The port wine lodges of Vila Nova de Gaia line the south bank of the Douro directly below the Ponte de Dom Luís I, their painted signs visible from the Porto side across the water. Taylor's, Graham's, Sandeman, Ferreira, Quinta do Crasto — almost every major port wine producer has a lodge here for aging and blending, and almost all of them offer tours and tastings.
The experience at any of the larger lodges follows a similar pattern: a walk through the barrel rooms (enormous, dark, fragrant with wine and oak), a brief explanation of how port is made and classified, and a tasting of two or three wines. Taylor's has particularly good educational content; Graham's tends to attract larger groups; the smaller lodges like Ramos Pinto or Barros offer a more personal experience. If you only have time for one, Taylor's cellar and tasting room combination is hard to beat. Booking ahead is advisable in summer. The Gaia embankment itself — the Cais de Gaia — has restaurants and bars with river views that are generally better value than the Porto side.