Queluz National Palace

The Palace of Queluz is an 18th-century palace located at Queluz, a city of the Sintra Municipality, in the Lisbon District, on the Portuguese Riviera. One of the last great Rococo buildings to be designed in Europe, the palace was conceived as a summer retreat for King José I's brother, Pedro of Braganza, later to become husband and king jure uxoris to his own niece, Queen Maria I. It eventually served as a discreet place of incarceration for Maria I, when she became afflicted by severe mental illness in the years following Pedro III's death in 1786.

Source: Wikipedia