Archaeologists have unearthed an ancient rectangular altar and an unfinished stela monument at the Chalcatzingo archaeological site in the central state of Mexico. According to Mexico's National Institute of Anthropology and History (INAH), experts estimate that the recently excavated remains have been made between 800 and 500 BCE.

The researchers also found similar remains around the site including about 44 altars, stelae and reliefs, all dating back to 2,500 years ago.

Another altar and a stela depicting three cats were found at Chalcatzingo site less than a year ago that belonged to the same age.

Stelae were monuments fashioned by the ancient civilizations often associated with low circular stones and were considered to be invested with holiness and to contain a divine soul-like essence.