Why weren’t people who visited Egypt able to see all of the Great Sphinx before 1936?

The Great Sphinx was largely covered in sand before 1936.

Explanation:

Despite being a well-known and famous statue, the Sphinx was largely hidden from view for centuries because of the desert sands that surround it. The area is subject to sandstorms and the local people lacked the engineering skills and the resources to try to unbury it and to regularly clear the monument of sand. In 1817 there were excavations by archaeologists and the chest of the Sphinx was uncovered. It was a man from France named Emil Baraize who unearthed all the sand from the larger structure so that the full body was revealed. Other archaeologists, engineers, and local people had tried to uncover it previously, but it was 1936 before Baraize was able to achieve it.

elastic potential energy