Palenque (Spanish pronunciation: [pa'leŋke]; Yucatec Maya: Bàakʼ [ɓaːkʼ]), also anciently known in the Itza Language as Lakamha ("big water" or "big waters"), was a Maya city-state in southern Mexico that perished in the 8th century. The Palenque ruins date from ca. 226 BC to ca. 799 AD. After its decline, it was overgrown by the jungle of cedar, mahogany, and sapodilla trees, but has since been excavated and restored. It is located near the Usumacinta River in the Mexican state of Chiapas, about 130 km (81 mi) south of Ciudad del Carmen, 150 meters (490 ft) above sea level. It is adjacent to the modern town of Palenque, Chiapas. It averages a humid 26 °C (79 °F) with roughly 2,160 millimeters (85 in) of rain a year.

Palenque is a medium-sized site, smaller than Tikal, Chichen Itza, or Copán, but it contains some of the finest architecture, sculpture, roof comb and bas-relief carvings that the Mayas produced. Much of the history of Palenque has been reconstructed from reading the hieroglyphic inscriptions on the many monuments; historians now have a long sequence of the ruling dynasty of Palenque in the 5th century and extensive knowledge of the city-state's rivalry with other states such as Calakmul and Toniná. The most famous ruler of Palenque was Kʼinich Janaabʼ Pakal, or Pacal the Great, whose tomb has been found and excavated in the Temple of the Inscriptions. By 2005, the discovered area covered up to 2.5 km² (0.97 sq mi), but it is estimated that less than 10% of the total area of the city is explored, leaving more than a thousand structures still covered by jungle. Palenque received 920,470 visitors in 2017.