Tiled churches, wines and the Douro river are the first things to encounter in Porto. Narrow streets and steep alleys will fascinate you at every trail you walk. The opposite town to Porto is Calem, the place which almost exclusively consists of old wine cellars, places where the Port wine was produced, with Sandemann, Calem and Offley wineries.
Porto has a unique selection of cafes, restaurants and bars. If you start diving into this scenery you are sure not to come up very soon. There are many expert restaurants to food an wine, offering the notorious Bacalhau, the Francesinha and the Caldeirada or Cataplana de peixe, the fish-pot that I can highly recommend.
At night Porto has a second life
Porto at daytime and Porto at night seem to be different towns. Fantastic illuminations and a vivid nightlife change the character of the town entirely. So seeing Porto only by day is knowing just one half of the town.
Scenic views in an excursion to the Douro Valley and Pinhão
If you find time, an excursion into the Douro valley is absolutely worth the way. You can do that by ship, by train or by car. If you do not have much time and if you want to see as much as you can, do take the train. A cruise from Porto takes hours and you see the wine yards only in the end. You usually also return by train in this case. If you can, choose a day that is sunny. The Douro valley will be double as beautiful.
Pinhão is a beautiful town (most beautiful rail station in Portugal) and the best starting point to many places. If you want to see more of the Duro valley you can take a boat cruise upstream. There are also many GPS-tracked hiking tours from Pinhão (German version).
Rooftops of Porto
If you stand at some higher point you get a scenic view over the roofs of Porto. Mosteiro Serra do Pilar, Torre dos Clérigos or Ponte Dom Luís would be good places to see Porto from above.