The Great Pyramid of Giza has been probed with the tools of modern particle physics by scientists who say they have discovered a huge, secret space hidden within its ancient walls.
It is located above a tall, cathedral-like room known as the Grand Gallery, and this newly found space is comparable in size — about 100 feet long, according to a report in the journal Nature.
That makes it a major structure within this royal tomb, which was built around 2500 B.C. and is considered to be one of the Seven Wonders of the Ancient World. Yet until now, despite centuries of study, no one knew this space was there.