Zona arqueológica "Pezuapan"

Pezuapan is what remains of a pre-Hispanic town now swallowed by Chilpancingo, in the Unidad Guerrerense district, known to everyone as INDECO, on the eastern slope of the valley. What survives is a stepped pyramid base about 50 metres a side and 12 metres high, inside a chain-link fence on a plot of half a hectare. It is the last piece of a settlement that once spread over some 80 hectares before the city grew over it.

The site came to light in 1982, when the INDECO housing agency was laying out the neighbourhood and a bulldozer tore into the pyramid. The state government halted the works and archaeologist Carlos Cedillo uncovered walls, floors and stairways, but residents keen to enlarge their lots knocked down the exposed remains at night, so the dig was backfilled and the plot spent years as a rubbish tip. A new INAH project managed to fence it in 1999; the stairs on the south face were cleared in 2004, and research and consolidation seasons followed from 2005, with help from the town council in 2006.

The settlement peaked between AD 800 and 1100, though it started earlier: its buildings and pottery tie it to the Mezcala culture, and from around AD 900 it shows Toltec influence. The main façade faces east, with a stairway flanked by smaller platforms built against its balustrades. Archaeologists have identified four building phases, in which older rooms were packed with earth to raise the floor, leaving some sealed rooms with walls up to 1.90 m high. Lime for the stucco floors and wall finishes was brought in from outside the valley, and the rooms at the foot of the pyramid, possibly administrative, yielded sea shell and alabaster.

Springs and the irrigated flats of the Huacapa River fed its people, and the town probably controlled the corridor between central Mexico and the Pacific coast. Burials turned up nearby, and in the San Francisco barrio a Tlaloc sculpture now kept at the Museo Regional de Guerrero. By the 15th century, when the Aztecs pushed into the valley, Pezuapan had been empty for centuries.