A small robot has discovered three possible burial chambers under a temple in Mexico's pre-Hispanic city of Teotihuacan, a find that may reveal secrets about funeral rituals in the ancient site.
The robot, dubbed Tlaloc II-TC, located the chambers in the last section of a 2,000-year-old tunnel tucked under the Temple of the Feathered Serpent, surprising archeologists who had expected to find just one room.
The National Anthropology and History Institute said the find could shed light on the burial rituals of the rulers of Teotihuacan, which is some 40 kilometers (25 miles) from Mexico City.
The mystery-filled ancient city is known for its majestic pyramids of the sun and the moon, but little is known about the people who inhabited the site. Teotihuacan, whose name means "City of Gods," had long been abandoned when Aztecs arrived in the area in the 1300s.
The tunnel under the Temple of Quetzacoatl, or Feathered Snake, was discovered after heavy rain uncovered a hole in the ground in 2003.
Tlaloc II-TC, named after the Aztec god of rain, was made to navigate rough terrain and is equipped with an infrared camera and a scanner that generates detailed maps.
The next step in the research will be to remove rubble blocking the last 30 meters (98 feet) of the 120-meter (394-foot) long tunnel, the anthropology institute said. Archeologists believe the obstruction hides a staircase that goes down three to four meters deeper below ground.
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