If you have the feeling that Lisbon might not be enough for you, then try a one day trip to Sintra and surroundings. Classified as a UNESCO World Heritage site, Sintra might be more than you bargained for. The royal retreats, estates, castles and other buildings, including views of the medieval Castelo dos Mouros, the Pena National Palace and the Sintra National Palace will take you by surprise. What you thought to be a simple one day trip from Lisbon, might hook you for your entire trip. At the western end of the Serra de Sintra mountain is also the most western point of Europe, Cabo da Roca. You might not want to leave.