Thebes was never a perfect position from which to rule Egypt. Perhaps that is why Memphis, even when it was not Egypt's capital, was nevertheless an important administrative center. Thebes really gained its importance as a religious center, along with the fact that it was an ideal location for an ancient Egyptian necropolis. The ancient Egyptians considered the west side of the Nile, was where the sun entered the netherworld, and was thus associated with the afterlife. The flat plain on the West Bank of the Nile River at Thebes stretched from the river to a mountain chain with numerous secluded valleys that threaded through tall, soft stone cliffs. 

What really made this site perfect was the aspect of mortuary temple and tomb combinations. Ever since the pyramid age, rulers of Egypt built a mortuary temple dedicated to their cult, together with their actual tomb. The West Bank at Thebes provided the flat plain they needed for the temple, while their tombs could be hewn from the limestone of the valleys beyond. 

Furthermore, the ravine that we call the Valley of the Kings was fairly remote, and with its narrow access, was easy to guard. However, symbolic attributes of the Valley were probably even more important. Viewed from the main city of Thebes on the east bank, the necropolis represented the "horizon" hieroglyph which was used by the ancient Egyptians to represent the area of the rising and setting sun. In fact, Deir el-Bahri, where Mentuhotep and Hatshepsut constructed their mortuary temples, with the Valley of the Kings directly beyond, sits at the center of the horizon point of this topographical akhet sign. In effect, the sun passes over the mortuary temples of the kings in the Nile Valley, then over the cliffs and down into the Valley of the Kings behind the western horizon, assimilating the king's passage with the solar cycle. Hence, the necropolis was directly linked to its symbolic purpose.

Another symbolism may have probably been the presence of el-Qurn, a pyramid shaped mountain known to the ancient Egyptians as dehenet. This peak is about 450 meters (1,500 feet) tall. It was sacred to the cow goddess Hathor, and later received its own cult following under the guise of the goddess Meretseger, "She who loves silence". However, it is also clear that the ancient Egyptians did not symbolically use this natural pyramid. Few efforts were made to quarry into its northern side, where the entrances to man made pyramids were located, and there were no efforts to align the tombs beyond with the various kings' mortuary temples in the Nile Valley. 

The Valley opens up at is narrowest point and runs west and northwest until it turns south before reaching its two main branches. The Valley of the Kings itself is actually made up of two separate wadis, or ravines, including the main eastern branch and a larger western branch. Most of the royal tombs are located in the smaller, eastern branch, which in ancient times was called ta set aat (the Great Place) or less formally ta int (the Valley), where they have traditionally been coded as KV (King's Valley). Today, the eastern branch is known as Biban el-Muluk (the Valley of the Doors of the Kings). This branch has several smaller branches where tombs may be found. These offshoots are usually named for these tombs, and include the Valley of the Tomb of Ramesses VII, which leads a short distance to the north, and the Valley of the Tomb of Ramesses XI, which branches off to the south. The few known tombs in the western branch, which obviously leaves the main branch in a westerly direction, may also be designated as having KV tombs, but are just as often referenced as WV (West Valley) tombs. It continues to the southwest through towing rock formations and ends in a large natural amphitheater where the rock walls rise dramatically above the desert plateau. There are many offshoots to this branch and were it not for Akhenaten, the heretic king, having located his first tomb here, more kings might have chosen this part of the valley for their tombs. 

Geology

Many thousands of years ago, the Nile Valley was an area of dynamic geology, where fluctuating ocean levels resulted in the Mediterranean Sea repeatedly covering the lower lying land, including much of what we call Egypt. Occasionally, the ocean stretched as far south as present day Aswan. 

This resulted in three distinct sedimentary rock formations which we refer to as the Dakhla chalk, Esna shale and Theban limestone, which dates from between 35 and 56 million years ago. What we see today when visiting the necropolis on the West Bank at Luxor (ancient Thebes) is primarily made up of these last two layers. The limestone formation is about 300 meters (1,000) feet thick from its highest point to where it meets the Esna shale, which in turn forms a band about 60 meters (200 feet) thick. Limestone is a sedimentary rock consisting chiefly of the mineral calcite, but it can also contain other constituents such as quartz, chert, clay, iron oxides, organics and dolomite. It is the most widely distributed of the carbonate rocks in the Earth's crust. Limestone in the Valley of the Kings varies from extremely fine and structurally sound to fractured and weak. This diversity can develop rapidly. For example, the stone in the tomb of Horemheb (KV57) is excellent, while only a few meters away, tomb KV11 is cut into extremely poor stone. In fact, during the quarrying of tombs, the workman would often pass through several layers of varying qualities of limestone, and the plans of the tombs may have sometimes been altered for this reason. 

We can actually see the zone where these two layers meet at a number of locations in the necropolis, including some tombs. For example, in the tomb of Seti I, the upper part of the burial chamber was cut from the limestone, while the lower part was quarried from the Esna shale. Unfortunately, the Esna shale in the valley is particularly weak and unstable. It not only posed problems to the ancient quarryman, but to the modern conservator as well. When the shale comes into contact with moisture, it expands and can literally tear a hill side apart. 

The geology of the Thebes necropolis was further affected by geological uplifting during the late Tertiary Period, as well as by erosion from the Nile inundation, as well as that of smaller tributaries during periods of increased rainfall, which occurred in the early Pleistocene era. During these wetter periods, there were thousands of streams snaking through the valley, scouring the Theban limestone as well as creating millions of tons of boulders, fragmented rock and sand. This formed the rough limestone cliffs we see today, together with the dry riverbeds that twist between them. 

Regrettably, the very geology that created the magnificent landscape of the West Bank now threatens to destroy its man made intrusions, namely the royal tombs. While the relatively soft rock of the valley was ideal for quarrying tombs, it is equally conducive to water intake and expansion. Hence, even the slightest rainfall in the surrounding high desert results in massive and disastrous flooding in the valley below. These flood waters, when uncontrolled, and sometimes even with man's best efforts to control them, scour and choke many of the royal tombs and damage the surrounding rock through penetration, expansion and uneven drying.

The ancient loss of ground water, along with the resulting earth movement has created a number of geological faults in the Valley. The largest of these is aptly named the Valley of the Kings Fault, which snakes along in an almost north-south line along the western side of the valley. With a displacement of almost 30 meters (100 feet) in some locations, though its average width is much less, it breaks the surface in a number of areas. One notable break is on the hillside above the tomb of Ramesses III. 

However, there are many smaller faults as well, some of which intersect with, and threaten the Royal tombs. In the tomb of Ramesses III, we find a fault in the left wall of the burial chamber that has allowed massive amounts of flood water to enter the lower half of this monument since the early part of the 1900s. There are also a number of open fissures, known as rock-joints to geologists, that spider the valley. Not truly considered faults, these geological features were often used by the quarrymen in the selection of a tomb site, and in cutting the tombs. 

Understanding the geology of the West Bank is an important aspect of understanding the original decisions for tomb location, as well as their modern conservation. Giovanni Belzoni appears to have been the first European to describe the basic geology and topography of the Valley of the Kings. He pointed out the drainage patterns which led to the positioning of some tombs. However, more recent work has established three groups of tombs that seem to be related geologically and hydrologically. They are also closely related to the three Egyptian dynasties that utilized the Valley of the King's as their necropolis.

For example, tombs that date from the early to the mid 18th Dynasty were usually quarried from the limestone clefts, and often, as in the case of the tomb of Tuthmosis III, beneath ancient waterfalls. After the burial took place, the entrances were walled over with stone and then plastered. Later, when flood waters poured into the Valley, they were buried beneath massive amounts of debris. 

During the late 18th Dynasty and throughout the 19th, the tombs are usually located further down the Valley some distance from the rock walls. The builders often quarried through talus slopes, such as in the case of the tomb of Amenhotep III. Another such tomb is that of Ramesses The Great (II), and it is clear from such examples that these tombs were much more susceptible to water damage. Since some of these tombs also make contact with the underlying shale, they are also prone to expansion damage. These tomb tend to be the worst preserved in the Valley.

Later, during the 20th Dynasty, the tombs were cut at ground level and often on the end of rock spurs produced by flood channels. These tombs have fared somewhat better than the late 18th and 19th Dynasty tombs, as their positioning gives some protection from flood waters. However, this is not to say that they remain undamaged, for water has often leaked in through their low lying entrances or through cracks in the surrounding rock. 

Modern agricultural processes have also added to the geological attributes of the Nile Valley basin. Today, ground water levels have risen in this area, and threaten low lying shaft tombs and the mortuary temples on the edge of the cultivation, as well as the well known Luxor and Karnak temples on the east bank.

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