Porto is iconic city of Portugal. The ideal place for 2-3 days-trip to get a great impression by culture, particular architecture, amazing food and wine. The unique sweetness of world famous porto wine made the city as the glorious center for wine lovers for many years.
Even it is only the second largest city in Portugal, but it feels much more authentic and traditional comparing to Lisbon. Moreover the city center has ideal size for walking activities despite on high heels and river in the middle. I bet you iPhone app will register record sum of elevation levels during the day.
The weather conditions are comfortable during whole year. Otherwise some warm clothes are recommended in winter, especially for sleeping. Old beautiful houses mostly has huge windows, which are so nice for summer, but making room temperature slightly lower than usual during winter.
Besides the current GoogleMaps list I recommend you to take small cruise upriver to Douro wine region. The views would be awesome!
One more tip - learn something about wine. Because the choice of manufactures and types of wine is huge. Do not hesitate to visit several manufactures for degustation/tours to find something suitable for you.
Here is list of attractions, cafe and restaurants in Porto for GoogleMaps.
PS. My previous posts with GoogleMaps lists: Istanbul, Helsinki, Tallinn, Riga.
