Where does it lead to?
Researchers have discovered a 30-feet-long unfinished corridor not far from the main entrance to the Great Pyramid of Giza in Egypt, Reuters reports — a breathtaking revelation, especially given the fact that we've been scanning the 4,500-year-old structure with infrared rays since 2015.
As detailed in a new article published in the journal Nature this week, the discovery made by the international research project Scan Pyramids could shed light on how the 479-foot-tall pyramid was constructed, and why the corridor is flanked by a massive limestone structure.
The corridor is only roughly 23 feet away from the pyramid's main entrance, which is crowded by tourists around the clock.
Most tantalizingly, we still don't know where the newly discovered tunnel even leads to.
"We're going to continue our scanning so we will see what we can do... to figure out what we can find out beneath it, or just by the end of this corridor," said Mostafa Waziri, head of Egypt's Supreme Council of Antiquities, as quoted by Reuters.
Researchers believe the corridor may have been built to redistribute the pyramid's weight around the main entrance. It was discovered using a tiny endoscope, using cosmic-ray radiography.
Many questions remain about the corridor's purpose, though.
"There are two large limestones at the end chamber, and now the question is what's behind these stones and below the chamber,'' Christian Grosse, Professor of Non-destructive Testing at the Technical University of Munich, told NPR.
The news comes after a giant void almost 100 feet in length was discovered by Scan Pyramids researchers back in 2017, the largest to have been discovered in the ancient structure in over a century.
This latest discovery could potentially force us to reevaluate what we know about how the giant structure was constructed many thousands of years ago — something that scientists still don't fully agree on, and a fascinating puzzle given its immense size and the ancient technology its builders had to rely on.
READ MORE: Hidden corridor discovered in Great Pyramid of Giza [Reuters]
More on the pyramids: Scientists Discover Egyptian Secret to Making the Pyramids