Portugal in December?

Vimla - Look into such towns like Lagos, Faro, Vilamoura, and Praia da Rocha in the Algarve region of Portugal. For a winter relaxing holiday, it is best to be based within the Algarve coastline, as this region offers the better weather. You can do Lisbon and the Algarve region or you can opt to do Algarve region of Portugal combine with Seville Spain and the surrounding Andalusian towns. Seville Spain from Algarve is about a 2 hour commute via Bus. The boys would enjoy the coastline towns of Portugal which have great beaches.

I wouldn’t describe the Algarve as exciting in winter. Many places are closed for the winter. It’s Southern Europe, so it won’t be particularly dark, but it could be very wet and it certainly won’t be beach weather.

Lagos and Tavira would be the best Algarve bases. Both retain some character, but have expanded rapidly over the past 20 years. Faro is a working city and not an interesting base IMO. Vilamoura is a soulless modern resort and marina. Praia da Rocha is a modern resort of high rise blocks. Silves or Loule would be smaller, slightly inland alternatives.

At that time of year, I would stick to Lisbon, as there is more to entertain all the family.

I don't think Lisbon is worth 9 days to stay as Jennifer mentioned. Vimla you have 9 days of vacation (Dec 24- Jan 3) so staying in one place would prevent you from discovering other places. Combine Lisbon with either the Algarve coastline towns or Seville Spain and the surrounding Andalusian towns to maximize your vacation days.

We stayed in Lisbon ten days and it was wonderful. But we also spent another ten days touring the rest of the country, skipping the Algarve.

You can easily spend 9 days in Lisbon by taking day trips to Evora, Cascais, Sintra, Obidos etc etc!

Thanks for all your replies! Planning a December trip with grumpy teens is stressful enough even without the rain! But I hope a few days in Lisbon and then some of the other cities mentioned in this conversation will be interesting enough for us to ignore the weather! After all we are from Seattle!
Some of the cities you mention sound so intriguing, Jennifer - Evora, Sintra, Obidos.. I plan to look them up. Personally, I am going for the murals, the Azuelejo tiles, Bertrand Bookstore and some less-mournful Fado!
Thanks a lot for all the answers and now I will start planning my trip!
Vimla

Since others have suggested Lisbon, I'll do the same and also add Porto!
We (parents with three adult children) spent last Christmas in Lisbon and Porto. Temps were 50s-60s with no rain. From Lisbon we had side trips to Cascais, Belem and Sintra. As we were in Lisbon the 24&25, it did limit sightseeing as things began to close xmas eve afternoon. We took a walking tour on Christmas Day as one of the few options available. We all really liked Time Out Market. We spent four nights in Lisbon and could have used another due to holiday closures. We took the train to Porto and spent three nights there. If your kids liked Harry Potter, there is a book store in Porto that JKRowlings based her library on. It is very popular, requires entrance ticket to enter and was packed with tourists taking pictures. It was also fun crossing the river and touring one of the wineries.
See what you can find on YouTube and in guide books and that may help you decide where to go. : )

Thanks, Susan. Porto sounds really interesting. I will start digging up info on Porto and see if I can fit it in our schedule. The Harry Potter book store you mention sounds really interesting! We would be fine if we spent all our time bookstore hopping in Portugal!
Thanks,
Vimla