It has taken technology almost two millennia to break one of the greatest secrets in the world of the ancient Americas.
Archaeologists have discovered ‘a recreation of the underworld’ at the ancient city of Teotihuacán in Mexico thanks to a radar device.
Researchers have only advanced 7 meters along the tunnel but the radar has revealed it to be 120 meters long and covered in symbols. It is thought that the passage leads to three chambers and may help explain the beliefs of the civilization.
Discovery: Archaeologists work inside a tunnel found under the ruins of the Feathered Serpent Temple at the archaeological site of Teotihuacán, near Mexico City
The tunnel, which is 13 meters below the ground, was originally discovered by chance in 2003 after heavy rains seeped into a tiny hole in the ground. No monarch’s tomb has ever been found at the site near Mexico City.
Sergio Gomez Chavez, an archaeologist at Mexico’s National Institute of Anthropology and History, said: ‘At the end, there are several chambers which could hold the remains of the rulers of that Mesoamerican civilization.
‘If confirmed, it will be one of the most important archaeological discoveries of the 21st century on a global scale.’
‘We know that Teotihuacán was built as a replica of how they saw the cosmos, the universe. We imagine the tunnel to be a recreation of the underworld.’
Ancient civilization: The Pyramid of the Sun (L) and the Avenue of the Dead in Teotihuacán
Secret chamber: It is believed that governors of the ancient city of Teotihuacán could be buried at the end of the tunnel below the Pyramid of the Feathered Serpent, also known as Quetzalcoatl
Teotihuacán, with its huge pyramids of the sun and moon, is made up of a labyrinth of palaces, temples, homes, workshops, markets and avenues.
The city is thought to have been built in 100BC and existed until the 8th century. Archaeologists consider it one of the most influential in pre-Hispanic North America, with a population of 200,000 at its peak.
Only 5 per cent of Teotihuacán has been excavated despite more than 100 years of exploration.
A small, remote-controlled robot — the first to explore Mexico’s ruins — took a camera inside a small opening in the tunnel before researchers finally entered last November.
Digging deep: Skilled workers search for archaeological pieces among remains from an excavation at the Temple of the Feathered Serpent
Significant: Mexican archaeologist Sergio Gomez Chavez believes the discovery could be one of the greatest of the 21st century
Some 30 experts work at the site, descending three ladders to get into the depths of the tunnel. They believe a deliberate effort was made to pile up stones and even pieces of a destroyed temple to block the entrance, some time between 200 and 300 AD.
Thermal imaging has become an essential part of archaeological digs. Last month, satellites helped locate 17 pyramids and 3,000 ancient settlements hidden underground in Egypt.
More than 1,000 burial sites were also discovered thanks to infra-red technology capable of probing beneath the desert sands from 450 miles above the Earth.
The mud bricks used by ancient Egyptians are much denser than the sand and soil that surrounds them, allowing the shapes of homes, temples, tombs and other structures built thousands of years ago to be seen by satellites that are invisible to the human eye.
Wonder: The pyramid at the ancient city of Teotihuacán where building began in 100BC
Unearthing the past: The impressive ceremonial architecture on the Temple of the Feathered Serpent reveals an ancient civilization steeped in tradition
A robot built at the University of Leeds also made new discoveries about the inner chamber of the Great Pyramid of Giza in Egypt.
Images captured by the ‘micro snake’ camera revealed small hieroglyphs written in red paint on the floor of a small, hidden chamber.
Egyptologists believe that if deciphered the markings could unlock the secrets of why tunnels, doors and secret chambers were built within pyramids.
Archaeologists made their discovery in the ancient city of Teotihuacán, north-west of Mexico City