If you are visiting Lisbon, I would highly recommend taking a day trip to Sintra. This is where you will find all the beautiful palaces and castles. It is only an hour train ride or a thirty minute drive from Lisbon. It’s definitely worth the visit!
There are so many beautiful sites spread across Sintra-Cascais Natural Park. We chose to visit Pena Palace. It is absolutely beautiful. I love all the colors and it literally feels like you are in a fairy tale.
I highly recommend you get there when it first opens. The lines get really long. The entrance fee is €14. You can also purchase tickets online and sign up for a guided tour.
The other popular sites to visit in Sintra are: Castle of the Moors, Quinta Da Regaleira, and Cabo da Roca. I definitely want to come back and visit these!