As previously mentioned, there is a huge park surrounding the Palácio de Pena. This collage just provide a glimpse.
The Sintra landscape is filled with palaces, forts and monastries. Besides, Sintra is an interesting town to visit. I have decided to budget 3 hours for the Pena visit, as the only one of all these grand buildings to visit and then I had to move on to cover the rest I wanted to, before booking in at Ericeira. I guess what I want to say, is that Pena is worth a full day's visit. Take along a picnic basket, as the park good for a lovely hike and some more treasures to discover.