Altar de Sacrificios is a ceremonial center and archaeological site of the pre-Columbian Maya civilization, situated near the confluence of the Pasión and Salinas Rivers (where they combine to form the Usumacinta River), in the present-day department of Petén, Guatemala. Along with Seibal and Dos Pilas, Altar de Sacrificios is one of the better-known and most intensively-excavated sites in the region, although the site itself does not seem to have been a major political force in the Late Classic period. Etymology The site was named by Teobert Maler, who thought that Stela 1 was used for sacrifices. Though an emblem glyph for the site has been identified, its phonetic reading has so far eluded epigraphers. Location Altar de Sacrificios is located on the Guatemalan side of the international border with Mexico, which follows the Salinas and Usumacinta rivers. It is upriver from the important Classic period Maya city of Yaxchilán and west of Seibal. The site is located on a small island located among seasonal swamps along the south bank of the Pasión River near where it joins the Salinas River (also known as the Chixoy River). This island measures approximately from east to west, with the ceremonial architecture located on the higher eastern end and the residential groups on the lower western end. History Archaeological investigations uncovered the long occupational history of the site and revealed that it was one of the earliest settlements in the Maya lowlands, having been founded before Tikal and other cities in the central Petén Basin, possibly by Mixe–Zoquean people who arrived from the west. This appears to have occurred around 800 BC, at the beginning of the Middle Preclassic period. Inhabitants lived at ground level in houses made of perishable materials, and had still not developed extensive trade networks. The site begins to show clearer evidence of use as a ceremonial center between 600 and 300 B.C., when houses begin to be built on terraces. Later in the Preclassic the site was settled by Maya peoples. The first pyramid (Structure B-1) in the Maya tradition dates from between 300 B.C. and 150 A.D. Also during this phase, traded jadeite and obsidian goods appear in burials. The site appears to have dominated the Usumacinta trade route circa 450 BC. Altar de Sacrificios enters the Classic Period between 150 and 550 A.D. Marine objects such as stingray spines and shell objects as well as obsidian,