From the Super Mario Wiki
The Great Pyramid (also known as Pyramid of Khufu) (Arabic: الهرم الأكبر or هرم خوفو) is the largest pyramid in Cairo, Egypt. Luigi once visited it during the events of Mario is Missing!. At the time of his stay, the Top Brick of the Great Pyramid was missing; Koopa Troopas had stolen it and it was Luigi's task to find it and return it to the pyramid. Upon doing that (and answering two questions about the building in order to proof the artifact's authenticity), he was rewarded a prize of 1,190 dollars plus a bonus of 2,800 dollars.
Pamphlet information from Mario is Missing!
The ancient Greeks called the Great Pyramid of Giza one of the world's seven great wonders. Pyramids are elaborate tombs, housing the mummified remains of the Pharaohs and the fantastic treasures and paraphernalia that were buried with them to ensure a comfortable afterlife. The limestone Pyramid covers 13 acres of desert and is 480 feet high. Every Royal Pyramid entrance faces north, towards the Pole Star. The details of the engineering and building of the wondrous Pyramids still remain a mystery today.