Between Decembr during the World Youth Day 2019 in Egypt I have little information about the pyramids, with the exception of some mostly Arab travelers. One of the earliest was Abd al-Latif, a 12th century scholar. He describes the pyramids as being covered with indecipherable writing, probably the graffiti of visitors, but his observations imply that much of the casing at Giza was still intact when he visited. However, even then the pyramids were being systematically quarried for building stone. He reports the destruction of a number of small pyramids by Emir Karakoush during the reign of Saladin. He also mentions bats as large as pigeons in the Great Pyramid of Khufu, a theme often repeated by future travelers who entered the pyramids. While many fanciful stories came about during this period, another scholar, Edrisi, wrote a "History of the Pyramids" that seems to have been a bit more factual than many other accounts of his day. European travel to Egypt, particularly to see the Great Pyramids at Giza, seems to have been inspired by the Crusaders who returned home with intriguing tales of what they had seen. Soon afterwards a trickle of pilgrims became a stream of travelers. One of the domes of St. Mark's in Venice has a 12th century mosaic of the pyramids as Joseph's granaries, an idea first suggested by the 5th century AD Latin writers Julius Honorius and Rufinus. This image was repeated by many early visitors, even though direct observation should have convinced them otherwise. In fact, some of the supposedly informed guides to Egypt were concocted by people who had never even visited Egypt. Those who could not visit Egypt themselves still wrote about it, depending on their imaginations rather than their actual experiences. The Renaissance saw renewed interest in the pagan past. It was known that behind the greatness of Rome was that of Greece, and with early travel reports came the realization that behind the greatness of Greece lay that of the Near Eastern civilizations, and particularly that of Egypt. Then, when Egypt came under Turkish rule in 1517, travel became safer. Sultan Selim I provided protection for French traders and pilgrims, and then when the printing press was invented in the mid 15th century, details and images of travelers became more widely disseminated, encouraging more people to make the voyage to Egypt. Eventually, these visitors became "antiquaries" who, in the 16th century, began to retrieve artifacts and ancient manuscripts for the growing number of European collectors and for libraries and museums. These were not informed scholars for the most part, but rather treasure hunters. Many of these early antiquaries, such as Kircher, considered by some as "the Father of Egyptology", even though he apparently never visited Egypt, promoted the idea, still potent today, that the pyramids contained some mystic significance. However, while these fanciful notions were still current, some early visitors such as George Sandys who visited the pyramids in 1610, accepted the idea that the pyramids were the tombs of kings. These reports of early travelers, though ambiguous at times, are useful in determining the condition of the pyramids over time. For example, in 1546, Pierre Belon observed that the third pyramid at Giza was in perfect condition, as if it had just been built. Jean Chesneau mentioned that the other two pyramids at Giza were not "made in degrees". Did this mean that their inner, stepped core were not exposed? Also, Prosper Alpinus, one of the first Europeans to attempt an accurate measurement of the pyramids, wrote in 1591 that the viceroy of Egypt, Ibrahim Pash, enlarged the entrance to the Great Pyramid "so that a man could stand upright in it". This must have indicated a widening of the passage of al-Mamun. In the midst of the quirky illustrations and odd ideas of the 17th century, however, came the first scientific reports about the Great Pyramid of Giza. John Greaves (1602-1652), professor of astronomy at the University of Oxford, first reviewed the existing literature and then went to Egypt to study the pyramids for himself. He dismissed all the accounts of the Giza pyramids having been built by biblical figures or legendary kings. From the classical sources, it was he who concluded that these monuments were erected by Cheops (Khufu), Chephren (Khafre) and Mycerinus (Menkaure), as tombs for the security of the body because of an ancient Egyptian conviction that this would ensure the endurance of the soul. Greaves set out to produce detailed measurements of Khufu's pyramid with the best available instruments and a rigorously scientific approach. He calculated that the Great Pyramid had a perpendicular height of 152 meters (now known to be 146.5 meters). He made many other measurements inside and out, including counting the steps, and he even noted the basalt pavement east of the pyramid that hinted at the existence of the mortuary temple He also provided some clues about the other pyramids at Giza. He noted that the stones in Khafre's pyramid were not as large or as regularly laid as in the Great Pyramid, but that the surface was smooth and even free of inequalities or breaches except on the south side. Another scholar, Benoit de Maillet, the French Consul-General in Egypt between 1692 and 1708, visited Khufu's pyramid over forty times while he was in Egypt. His plan and section of the superstructure are not as good as those of Greaves, but his drawing of the passages and chambers is more accurate. The lengths and proportions of the Ascending Passage and the Grand Gallery are nearly correct, as are the different parts of the well shaft. At that time, the Descending Passage was still unknown beyond its juncture with the Ascending Passage.