In the Pena Palace, in the municipality of Sintra, on the Portuguese Riviera

 (in São Pedro de Penaferrim, in the municipality of Sintra, on the Portuguese Riviera) The Pena Palace (Portuguese: Palácio da Pena) is a Romanticist castle on the Portuguese Riviera. The castle stands on the top of a hill in the Sintra Mountains above the town of Sintra, and on a clear day it can be easily seen from Lisbon and much of its metropolitan area. It is a national monument and constitutes one of the major expressions of 19th-century Romanticism in the world. The palace is one of the Seven Wonders of Portugal. (It is also used for state occasions by the President of the Portuguese Republic and other government officials).

+ The castle's history started in the Middle Ages when a chapel dedicated to Our Lady of Pena was built on the top of the hill above Sintra. According to tradition, construction occurred after an apparition of the Virgin Mary. In

1493, John II, accompanied by his wife Leonor of Viseu, made a pilgrimage to the site to fulfill a vow. His successor, Manuel I, was also very fond of this sanctuary, and ordered the construction of a monastery on this site which was donated to the Order of Saint Jerome. For centuries Pena was a small, quiet place for meditation, housing a maximum of eighteen monks. In the 18th century the monastery was severely damaged by lightning. However, it was the 1755 Lisbon earthquake, occurring shortly afterwards, that took the heaviest toll on the monastery, reducing it to ruins. Nonetheless, the chapel (and its works of marble and alabaster attributed to Nicolau Chanterene) escaped without significant damage.

+ For many decades the ruins remained untouched, but they still astonished young Prince Ferdinand. In 1838, as King consort Ferdinand II, he decided to acquire the old monastery, all of the surrounding lands, the nearby Castle of the Moors and a few other estates in the area. King Ferdinand then set out to transform the remains of the monastery into a palace that would serve as a summer residence for the Portuguese royal family. The commission for the Romantic style rebuilding was given to Lieutenant-General and mining engineer Wilhelm Ludwig von Eschwege. Eschwege, a German amateur architect, was much traveled and had knowledge of several castles along the Rhine river. The construction took place between 1842 and 1854. Ferdinand and Queen Maria II, however, intervened decisively on matters of decoration and symbolism. Among others, the King suggested vaul  arches, Medieval and Islamic elements be included.

+ In 1889 it was purchased by the Portuguese state, and after the Republican Revolution of 1910 it was classified as a national monument and transformed into a museum. The last queen of Portugal, Queen Amélia, spent her last night at the palace before leaving the country in exile.
The palace quickly drew visitors and became one of Portugal's most visited monuments. In 1995, the palace and the rest of the Cultural Landscape of Sintra were classified as a World Heritage Site by UNESCO.