While it is technically possible to visit both Sintra and Óbidos in a single day from Lisbon, it is generally not recommended if you want to truly experience either location. Sintra is a UNESCO World Heritage site with multiple major landmarks—such as the Pena Palace, the Moorish Castle, and Quinta da Regaleira—which are spread across steep hills and often require a full day of walking and waiting in lines. Óbidos, a stunning medieval walled village, is about an hour's drive north of Lisbon and deserves several hours of leisurely exploration. Trying to combine them typically involves a 10-to-12-hour "marathon" tour where you might only see one palace in Sintra before rushing off to Óbidos. Most travelers in 2026 find that the "sweet spot" is to dedicate one full day to Sintra's castles and a separate half-day to Óbidos, perhaps combining the latter with a visit to the nearby surf town of Peniche or the monster waves of Nazaré for a more balanced Portuguese itinerary.