Sintra feels like a storybook town. Old palaces sit on green hills. Fog rolls in some mornings and lifts into bright sun. The air is cool and fresh most of the year. I loved wandering stone streets after work.
For digital nomads it is peaceful. Internet in cafés is usually solid and many apartments have fiber. Mobile signal can drop up near the castles. Cost of living is lower than big cities but higher than small Portuguese towns. For some this will be perfect. For budget nomads there are cheaper spots.
Things to do are endless. Hike to Pena Palace. Explore Quinta da Regaleira. Hit the nearby beaches. I once read people play beach volley at Praia das Maçãs and that sounds fun. The expat and nomad crowd is small but friendly. Big meetups are an easy train ride to Lisbon. Most travellers enjoy the slow vibe here. It is charming, not flashy, and you might just get inspired to work with a view.