Mixco Viejo

The ruins are strung out over 1 kilometre (0.62 mi) along a 880-metre (2,890 ft) high ridge in the municipality of San Martín Jilotepeque, surrounded by deep ravines that drop sharply into a tributary of the Pixcaya River. The site is 53.3 kilometres (33.1 mi) from Guatemala City by road. It consists of 15 groups, labelled A to L by archaeologists, containing the remains of over 120 major structures, including temples, palaces and courts for the Mesoamerican ballgame. The city originally had its main entrance on the western side.

The architecture was built with mica and pumice slabs, in some cases coated with stucco. Stone sculpture is almost totally absent; the only example is a ballcourt marker in the form of a serpent's head with jaws agape and a human head emerging from its mouth. Some buildings were decorated with painted stucco, but only a few fragments remain. The relatively short period of occupation led to an unusual unity of architectural styles for a Mesoamerican city.

Group A lies at the northern end of the ridge. Pyramid A1, one of its principal structures, is 6.9 metres (23 ft) high and measures 15.4 by 7.25 metres (50.5 by 23.8 ft) at the base. It was built of cut stone, has four stepped levels each ending in a cornice, and faces west onto the plaza with two stairways of 27 steps each, flanked by smooth balustrades. Its summit supports a 60-centimetre (24 in) high platform that once formed the base of a summit temple. The pyramid was built over an earlier two-level stucco platform. Platforms A2 and A3 were each built in successive versions, the final ones after a new retaining wall some 12 metres (39 ft) further out had been built and the area behind it filled in to create an expanded terrace.

Around 1450 the Chajoma, led by their king Lajuj No'j, moved to the site from Ochal to make their capital more inaccessible to hostile neighbours. In spite of this, the Kaqchikel kingdom of Iximche defeated the Chajoma and the city became subject to it. Groups C and E show Kaqchikel influence in their architecture, while groups A and B have a purer Chajoma style, and both ballcourts appear to have been remodelled in the Kaqchikel fashion with thick coatings of stucco. Shortly before the Spanish conquest the Chajoma under their lord Achi Q'alel rebelled against the Kaqchikels of Iximche.

The Chajoma may initially have allied themselves with the Spanish together with Iximche, and may have joined the general Kaqchikel uprising in 1524. When the lords of Iximche broke their alliance with the conquistadors, they took refuge in Jilotepeque. The site was abandoned after the Spanish conquest, its inhabitants were moved to San Martín Jilotepeque, and the area was never reoccupied. Almost all archaeological finds, including earlier versions of later structures, date to the last few hundred years before the conquest. A population estimate based on residential remains gives approximately 1450 to 1600 inhabitants.

Traces of charcoal at the base of the old retaining wall of Group A have been radiocarbon dated to the 13th century, indicating that the expansion of Group A took place no earlier than that. Because the group has two ballcourts, it is possible that the city served as a regional centre for the ballgame during the Postclassic.