According to forum posts, Avenida da Liberdade is a recommended area to stay due to its proximity to major sights and quietness at night, making it suitable for those who prefer a peaceful sleep. Travelers have called out this area for being both central and accessible while avoiding the noisy nightlife of districts like Alfama and Bairro Alto.

Some travelers suggest staying in residential areas like Campo de Ourique, which, despite not being on the metro line, offers good bus connectivity and a local vibe with plenty of cafes and stores. This area is appreciated for its authenticity and quieter environment compared to the bustling tourist spots.

Posts also indicate Belem as an interesting option, particularly for those interested in cultural sites. It is well-connected by public transport, including trams and buses to central Lisbon, and offers attractions such as museums and historical sites. However, some users note that while Belem is rich in attractions, it might not be as centrally convenient for all travelers.

According to forum posts, Sintra is easily accessible by train from Lisbon with frequent services departing from several stations including Rossio and Oriente. The journey takes about 40 minutes. Alternatively, travelers have mentioned the possibility of using Uber for direct transport to Sintra, which could be effective especially during rush hours or strikes.

Some travelers suggested that Sintra has numerous attractions that are spread out, making it challenging to see everything in one day. It's recommended to prioritize which sites to visit, such as Pena Palace or Quinta da Regaleira, and consider using the local bus system which connects major sites. Tickets for popular sites like Pena Palace should be purchased in advance to avoid long wait times.

Forum users also recommend checking the train schedules and potential strikes on the official CP (Comboios de Portugal) website to ensure smooth travel plans. For a hassle-free experience, consider starting the trip early in the day to maximize sightseeing time and avoid crowds.