I am interested in doing the RS Portugal trip in 2018 and searching opinions on when the best time is to be in Portugal: spring? mid summer? fall? What's you opinion? Would also like to add on a week before or after. What shouldn't we miss that isn't included on the tour?
Not the summer! The crowds have gotten worse in the last couple of years and, depending on where you are, it can be very hot. There are more chances for rain in the spring or fall but there are fewer people and the temps are generally very nice.
As far as where to go other than the tour - I don't know where the RS tours go, but they likely hit the bigger places. You might want to get a Lonely Planet and read it. It will cover more of the country than RS does.
Julie Dawn Fox does a blog about Portugal and focuses a significant amount on the lesser known areas of the country.
The 12-day Portugal tour itinerary doesn't include these destinations, though they are covered in Rick's Portugal book:
- Sintra (If you would like to visit Sintra as a day trip from Lisbon, we recommend that you include time before your tour starts.)
- The Algarve region of the south coast
You could also head north from Porto to Santiago de Compostela in Spain. The only attractive train connection departs about 8:15 a.m., 5 hours with a connection in Vigo. A direct, daily noontime bus operated by www.alsa.es (4 hours) is simpler.
Late May/early June or mud September are my favourite times to visit Portugal - no school children and a reasonable chance of good weather.
The Algarve is mainly about beaches and golf and if these aren't of primary interest, you would be best visiting other parts of the country. I like the Alentejo - great countryside and traditional towns.