To form a serdab in the solid rock was almost impossible; while on the other hand, movable statues, if left in a room accessible to all comers, would be exposed to theft or mutilation.
When space permitted, the vault was excavated immediately below the chapel. The shaft was sometimes sunk in a corner of one of the chambers, and sometimes outside, in front of the door of the tomb. In the great cemeteries, as for instance at Thebes and Memphis, the superposition of these three parts--the chapel, the shaft, and the vault--was not always possible. If the shaft were carried to its accustomed depth, there was sometimes the risk of breaking into tombs excavated at a lower level. This danger was met either by driving a long passage into the rock, and then sinking the shaft at the farther end, or by substituting a slightly sloping or horizontal disposition of the parts for the old vertical arrangement of the mastaba model. The passage in this case opens from the centre of the end wall, its average length being from 20 to 130 feet. The sepulchral vault is always small and plain, as well as the passage. Under the Theban dynasties, as under the Memphite kings, the Soul dispensed with decorations; but whenever the walls of the vault are decorated, the figures and inscriptions are found to relate chiefly to the life of the Soul, and very slightly to the life of the Double. In the tomb of Horhotep, which is of the time of the Ûsertesens, and in similar rock-cut sepulchres, the walls (except on the side of the door) are divided into two registers. The upper row belongs to the Double, and contains, besides the table of offerings, pictured representations of the same objects which are seen in certain mastabas of the Sixth Dynasty; namely, stuffs, jewels, arms, and perfumes, all needful to Horhotep for the purpose of imparting eternal youth to his limbs. The lower register belonged to both the Soul and the Double, and is inscribed with extracts from a variety of liturgical writings, such as The Book of the Dead, the Ritual of Embalmment, and the Funeral Ritual, all of which were possessed of magic properties which protected the Soul and supported the Double. The stone sarcophagus, and even the coffin, are also covered with closely-written inscriptions. Precisely as the stela epitomised the whole chapel, so did the sarcophagus and coffin epitomise the sepulchral chamber, thus forming, as it were, a vault within a vault. Texts, tableaux, all thereon depicted, treat of the life of the Soul, and of its salvation in the world to come.
At Thebes, as at Memphis, the royal tombs are those which it is most necessary to study, in order to estimate the high degree of perfection to which the decoration of passages and sepulchral chambers was now carried. The most ancient were situated either in the plain or on the southern slopes of the western mountain; and of these, no remains are extant. The mummies of Amenhotep I., and Thothmes III., of Sekenenra, and Aahhotep have survived the dwellings of solid stone designed for their protection. Towards the middle of the Eighteenth Dynasty, however, all the best places were taken up, and some unoccupied site in which to establish a new royal cemetery had to be sought. At first they went to a considerable distance, namely, to the end of the valley (known as the Western Valley), which opens from near Drah Abû'l Neggeh. Amenhotep III., Aï, and perhaps others, were there buried. Somewhat later, they preferred to draw nearer to the city of the living. Behind the cliff which forms the northern boundary of the plain of Thebes, there lay a kind of rocky hollow closed in on every side, and accessible from the outer world by only a few perilous paths. It divides into two branches, which cross almost at right angles. One branch turns to the south-east, while the other, which again divides into secondary branches, turns to the south-west. Westward rises a mountain which recalls upon a gigantic scale the outline of the great step-pyramid of Sakkarah (fig. 137). The Egyptian engineers of the time observed that this hollow was separated from the ravine of Amenhotep III. by a mere barrier some 500 cubits in thickness. In this there was nothing to dismay such practised miners. They therefore cut a trench some fifty or sixty cubits deep through the solid rock, at the end of which a narrow passage opens like a gateway into the hidden valley beyond. Was it in the time of Horemheb, or during the reign of Rameses I., that this gigantic work was accomplished? Rameses I. is, at all events, the earliest king whose tomb has as yet been found in this spot. His son, Seti I., then his grandson, Rameses II., came hither to rest beside him. The Ramesside Pharaohs followed one after the other. Herhor may perhaps have been the last of the series. These crowded catacombs caused the place to be called "The Valley of the Tombs of the Kings,"--a name which it retains to this day.
These tombs are not complete. Each had its chapel; but those chapels stood far away in the plain, at Gûrneh, at the Ramesseum, at Medinet Habû; and they have already been described. The Theban rock, like the Memphite pyramid, contained only the passages and the sepulchral chamber. During the daytime, the pure Soul was in no serious danger; but in the evening, when the eternal waters which flow along the vaulted heavens fall in vast cascades adown the west and are engulfed in the bowels of the earth, the Soul follows the bark of the Sun and its escort of luminary gods into a lower world bristling with ambuscades and perils. For twelve hours, the divine squadron defiles through long and gloomy corridors, where numerous genii, some hostile, some friendly, now struggle to bar the way, and now aid it in surmounting the difficulties of the journey. Great doors, each guarded by a gigantic serpent, were stationed at intervals, and led to an immense hall full of flame and fire, peopled by hideous monsters and executioners whose office it was to torture the damned. Then came more dark and narrow passages, more blind gropings in the gloom, more strife with malevolent genii, and again the joyful welcoming of the propitious gods. At midnight began the upward journey towards the eastern regions of the world; and in the morning, having reached the confines of the Land of Darkness, the sun emerged from the east to light another day. The tombs of the kings were constructed upon the model of the world of night. They had their passages, their doors, their vaulted halls, which plunged down into the depths of the mountain. Their positions in the valley were determined by no consideration of dynasty or succession.
Each king attacked the rock at any point where he might hope to find a suitable bed of stone; and this was done with so little regard for his predecessors, that the workmen were sometimes obliged to change the direction of the excavation in order not to invade a neighbouring catacomb.