Palenque

A Maya city in the Chiapas jungle, occupied from about 226 BC to AD 799, and the place where in 1952 Alberto Ruz Lhuillier lifted a slab in the Temple of the Inscriptions, found a staircase packed with rubble, cleared it over four seasons and came out at the bottom in the tomb of K’inich Janaab’ Pakal, sealed since AD 683. Jade mosaic mask, jade ornaments, one of the richest pre-Columbian burials ever properly excavated, and a five-tonne carved sarcophagus lid that has been the subject of more nonsense than almost any other Maya object. The pyramid over it is 60 by 42.5 metres and 27.2 high. And here is the part that should get you on a plane: by 2005 about 2.5 square kilometres had been uncovered and that is estimated at under ten percent of the city. Over a thousand structures are still under the trees. UNESCO listed it in 1987.