Mexican archeologists have made the most significant Aztec find in decades, unearthing a 15th century altar and a huge stone slab at a ruined temple in the throbbing heart of Mexico City.
The works were uncovered last weekend at the Aztec empire's main Templo Mayor temple, near the central Zocalo square, which was used for worship and human sacrifice.
It was the most meaningful find since electricity workers stumbled upon an eight-tonne carving of an Aztec goddess at the same site in 1978.
"It is a very important discovery, the biggest we have made in 28 years. It will allow us to find out a lot more," Mexico City's mayor, Alejandro Encinas, said today.
The altar has a frieze of the rain god Tlaloc and and an agricultural deity.
Archeologists are still unearthing the 11-foot (3.5-m) monolith, which they think might be part of an entrance to an underground chamber.
At the site, excavators with pick axes and shovels hacked at the earth above the monolith while groups of archeologists, government officials and reporters waited around the deep pit.
"The importance of the monolith is what we are going to discover...It's likely that it is part of a chamber, of some offering. We won't know until we get close. First we have to get the stone out," said Alberto Diaz, a member of the archeological team.
The Aztecs, a warlike and deeply religious people who built monumental works, ruled an empire stretching from the Gulf of Mexico to the Pacific Ocean and encompassing much of modern-day central Mexico.
Their often bloody reign began in the 14th century and ended when they were subjugated in 1521 by the Spanish led by Hernan Cortes.