Yes, Sintra offers a very efficient "hop-on hop-off" style service, though it is operated by the local public bus company, Scotturb, rather than the traditional open-top red buses seen in major cities. The most famous routes are Bus 434 (the Pena Circuit) and Bus 435 (the Villa Express 4 Palaces). For a fixed daily price—typically around €13.50 as of 2026—you can purchase a 24-hour ticket that allows you to hop on and off as many times as you like. Route 434 is essential for most tourists as it connects the Sintra Train Station to the steep, winding climb up to the Moorish Castle and the colorful Pena Palace. Walking this route is extremely difficult due to the incline and lack of sidewalks. Route 435, meanwhile, focuses on the town center and other architectural gems like Quinta da Regaleira, Seteais Palace, and Monserrate Palace. These buses are designed specifically for the narrow, one-way roads of the Sintra hills where standard cars often get stuck in gridlock. Buying the ticket online usually offers a small discount, and it saves you the hassle of paying the driver for individual trips. It is the gold standard for navigating Sintra's UNESCO World Heritage sites without the stress of driving or the exhaustion of hiking between distant palaces.