The Great Pyramid of Giza, built in Egypt’s Old Kingdom, has endured for millennia as a monument to human ambition, standing unchanged as civilizations rose and fell.

Researchers now have discovered one of the reasons for its astonishing durability - it was designed and built with structural features that have helped it withstand the destructive energy of earthquakes since its construction about 4,600 years ago as the tomb of the pharaoh Khufu.

The scientists assessed its structural dynamics by using devices called seismometers to record ambient vibrations - continuous subtle background shaking generated by natural forces and human activity - at 37 locations in and around the pyramid. It exhibited a remarkably homogeneous and stable structural response to these vibrations despite its size and complexity.

The scientists identified several characteristics that gave the pyramid earthquake resistance. It has an extremely broad base with low center of gravity, highly symmetrical geometry, a gradual reduction in mass toward the top and sophisticated internal design including internal chambers that blunt vibration amplification. It also was constructed on strong limestone bedrock.

The four sides of the pyramid, located in Giza right outside the Egyptian capital Cairo and built of massive limestone blocks, each measure about 755 feet (230 meters) at the base, and it covers about 13 acres (5.3 hectares).

It originally stood about 480 feet (147 meters) tall. Natural erosion over time and the removal centuries ago of its smooth outer casing stones for building material left it at its current height of approximately 455 feet (138.5 meters). It was the world’s tallest structure for some 3,800 years.