Ancient Entrance to the Underworld discovered in Teotihuacan, Mexico (Video)

Mexican archaeologists say powder-glittered tunnel filled with ritual objects may lead to royal tombs in the ancient Mexican city of Teotihuacan.

A sacred tunnel discovered in the ancient Mexican city of Teotihuacan is filled with thousands of ritual objects and may symbolize an underworld that leads to royal tombs, the lead Mexican archaeologist on the project said on Wednesday (October 29, 2014).

The entrance to the 1,800 year-old tunnel was first discovered in 2003, and some of its contents later came to light thanks to excavations by remote-control robots and then human researchers, archaeologist Sergio Gomez told reporters.

The site is located about 30 miles (50 kilometers) northeast of Mexico City and the ruins have long been shrouded in mystery as its inhabitants did not leave behind written records.

Gomez, who works for Mexico's national anthropology and history institute, said ongoing excavations could yield more major discoveries next year.

"It (the excavations) will allow us to better understand much better how the society in Teotihuacan was structured from its beginnings. What were the changes that took place around 200 - 250 A.C., which is when we have noticed that something happened or was happening in Teotihuacan that changed the story of the city," he said.

Gomez said the powder glittered tunnel, located below the Temple of the Plumed Serpent, was created to evoke a different world.

"The walls and domes of the tunnel were covered with a dust made out of metallic mineral, like pyrite, magnetite. They ground it up to make some kind of powdered glitter and they coated it on the roof, walls and floor, making us imagine that when they lit a torch, the whole place lit up and as we have seen, it looks as though you are seeing the sky and the stars shinning. This whole construction, which was an exceptional accomplishment and an effort of large-scale proportions, was done to recreate the conditions of how they imagined the underworld," he said.

The artifacts found inside the tunnel include finely carved stone sculptures, jewelry and shells.

An estimated 50,000 objects, 4,000 made of wood as well as scores of obsidian blades and arrow heads, provide clues into how the city's priests and rulers conceived the underworld.

One of Mexico's most-visited ancient sites, Teotihuacan is home to massive pyramids, temples and elite residences including many adorned with colorful murals.

The city reached its peak between 100 B.C. and 650 B.C. with a population as large as 200,000, growing rich from a wide-ranging trade in obsidian which in pre-Colombian times was used to make knives and other weapons.

The city had long been abandoned by the time the Aztecs came to power in the Valley of Mexico in the 14th century, yet it continued to play an important role as a destination for religious pilgrimages.

In Nahuatl, the Aztec language still spoken in many parts of Mexico, Teotihuacan means "abode of the gods."