To maximize your visit to Sintra, you should aim to arrive at the Sintra Train Station no later than 8:30 AM or 9:00 AM. This allows you to be at the gates of your first major attraction—usually the Pena Palace or the Quinta da Regaleira—as soon as they open at 9:30 AM. Arriving early is crucial because Sintra is one of the most visited destinations in Portugal; by 11:00 AM, the narrow, winding roads become clogged with tour buses, and wait times for the popular "434" tourist bus can exceed 45 minutes. By starting early, you can explore the upper gardens and palace interior of Pena before the midday crowds and heat arrive, then work your way down to the Moorish Castle or the town center for lunch. If you arrive late in the afternoon, you risk missing out on several sites, as most palaces close their gates between 5:30 PM and 6:30 PM. For those staying in Lisbon, catching the 7:40 AM or 8:11 AM train from Rossio Station is the best strategy to ensure you stay ahead of the massive influx of day-trippers that typically arrives around 10:30 AM.