Yes, doing Sintra without a tour is not only possible but is often the preferred way for independent travelers to experience the region in 2026. To do it successfully, you should take the direct train from Lisbon’s Rossio Station (approx. 40 minutes, €2.45), which drops you right in the heart of the town. From there, you can use the 434 Tourist Bus, which follows a one-way loop connecting the train station, the Historic Center, the Moorish Castle, and the iconic Pena Palace. An independent trip allows you to set your own pace—for instance, arriving at Pena Palace the moment it opens at 9:00 AM to beat the massive tour bus crowds. You can also choose exactly which palaces to visit, such as the mystical Quinta da Regaleira or the quieter Monserrate Palace. The key to a "tour-free" success is booking all tickets online in advance and arriving early; by mid-morning, the bus lines and ticket queues can be hours long. With a 24-hour bus ticket (€13.50) and a bit of planning, you can see all the highlights of this "landscape of palaces" for a fraction of the cost of a guided tour.