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. Following the destruction of Ajuda Palace by fire in 1794, Queluz Palace became the official residence of the Portuguese Prince Regent João, and his family, and remained so until the royal family fled to the Portuguese colony of Brazil in 1807, following the French invasion of Portugal.

Sintra is a town and municipality in the Greater Lisbon region of Portugal, located on the Portuguese Riviera. The population of the municipality in 2021 was 385,654, in an area of 319.23 square kilometres (123.26 sq mi). Sintra is one of the most urbanized and densely populated municipalities of Portugal. A major tourist destination famed for its picturesqueness, the municipality has several historic palaces, castles, scenic beaches, parks and gardens.