Egyptian antiquities officials say they have confirmed the existence of a hidden internal corridor above the main entrance to the Great Pyramid of Giza.
Borescope video showed the interior of the hallway, which is 9m (30ft) long and 2.1m (7ft) wide.
Officials say it could have been created to redistribute the weight of the pyramid around the entrance or another yet unknown chamber.
It was first detected in 2016 using an imaging technique called muography.
The non-invasive technique detected an empty space behind the north face of the Great Pyramid, about 7m above the main entrance, in an area where there is a stone rafter structure.
Further tests were carried out with radar and ultrasound before a 6 mm wide (0.24 inch) borescope was fed through a tiny joint between the stones that make up the rafters.
The camera footage was unveiled at a press conference next to the pyramid on Thursday. It showed an empty hallway with walls made of roughly hewn stone blocks and a vaulted stone ceiling.
“We will continue our analysis to see what we can do…to understand what we can discover below, or just down this corridor,” said Mostafa Waziri, head of Egypt’s Supreme Council. of Antiquities.
The Great Pyramid, which is 146m high, was built on the Giza Plateau during the Fourth Dynasty by Pharaoh Khufu, or Cheops, who ruled from around 2609 BC to 2584 BC.
Although it is one of the oldest and largest monuments on the planet, there is no consensus on how it was built.
Egyptian archaeologist Zahi Hawass said the hallway represented a “major find” that would “enter the homes and homes of people around the world for the first time”.
He also said it could help reveal if King Khufu’s burial chamber still existed inside the pyramid.
He speculated there might be ‘something important’ in the space below the hallway, then added: ‘I’m sure in a few months we can see if what I’m saying is correct or not.”