We will be in Lisbon only one short day on a cruise. I really want to see Sintra, but does it make sense with only one day in Lisbon or are there other must-see sights we should see instead?

You will get different opinions, but we toured Lisbon, took a day trip to Fatima and stayed in Sintra, and we did not regret that. The three palaces in Sintra were fabulous and Sintra is a nice little town. Do not miss Quinta da Regaleira, especially the grounds, park, tunnels, waterfalls. It will put a smile on your face.

There is so much to see in Lisbon I would not bother with Sintra. I would rate the Jeronimos monastery in Belem the top sight, followed by the Gulbenkian museum, but it is a good city for strolling and hanging out as well. Click on my name for my profile to find my Lisbon TR.

I agree with thursdaysd, if you only have 1 day stay in Lisbon. Visit the Belém área, Chiado Square, walk down to Terreiro do Paço Square and to Alfama.

I would stay in Lisbon! And I suggest visiting the Sao Jorge Castle with its gorgeous views, and then spend time slowly wandering through the Alfama. There are fewer tourists as you walk further away from the castle. We followed Rick Steves walking tour of the Alfama, after visiting the Castle, and it was our best day in Lisbon. The Alfama is the oldest neighborhood in Lisbon because it was not destroyed during the 1755 earthquake. There are lots of stairs, up and down walking, and narrow, twisty alleyways. People live here. We saw clothes hanging to dry on balconies; we heard radios and tv's coming from open windows, and saw children riding their bikes.An elderly lady set up shop with a small table under a shade tree selling gingrinja, the sour cherry liquer. We enjoyed the Jeronimos Monastery and Belem, but our best day was at the castle and Alfama.

I agree with whitehall, actually. The train takes only an hour(the Oriente Station is convenient to the airport). Quinta de Regaleira is 10 minutes by taxi from the station or you can take the bus. The Sintra Palace is right in the center of town, you can view the exterior without a ticket. The Pena Palace is also pretty fab.

It can take an hour just to wait in line for a ticket to either of those Lisbon sites, and it also takes a while to get to Jeronimos in Belem.

Is it impossible to add any more time?