Which pyramids are in cairo

It's likely that communities across Egypt contributed workers, as well as food and other essentials, for what became in some ways a national project to display the wealth and control of the ancient pharaohs. Such revelations have led Zahi Hawass , secretary general of Egypt's Supreme Council of Antiquities and a National Geographic explorer-in-residence, to note that in one sense it was the Pyramids that built Egypt—rather than the other way around.

If the Pyramids helped to build ancient Egypt, they also preserved it. Giza allows us to explore a long-vanished world. Tomb art includes depictions of ancient farmers working their fields and tending livestock, fishing and fowling, carpentry, costumes, religious rituals, and burial practices.

Inscriptions and texts also allow research into Egyptian grammar and language. To help make these precious resources accessible to all, Der Manuelian heads the Giza Archives Project, an enormous collection of Giza photographs, plans, drawings, manuscripts, object records, and expedition diaries that enables virtual visits to the plateau. Older records preserve paintings or inscriptions that have since faded away, capture artifacts that have been lost or destroyed, and unlock tombs not accessible to the public.

Armed with the output of the longest-running excavations ever at Giza, the Harvard-Museum of Fine Arts, Boston Expedition , Der Manuelian hopes to add international content and grow the archive into the world's central online repository for Giza-related material.

But he stresses that nothing could ever replicate, or replace, the experience of a personal visit to Giza. Tourism to the structures has declined rapidly since the advent of the Arab Spring in , when Egypt experienced a political upheaval that lasted years.

The country has since been through several administration changes, and the instability means the future of tourism to the Pyramids is uncertain. All rights reserved. Building Boom The ancient engineering feats at Giza were so impressive that even today scientists can't be sure how the pyramids were built.

Preserving the Past If the Pyramids helped to build ancient Egypt, they also preserved it. Share Tweet Email. Thus was the social order perpetuated throughout eternity and the forces of primeval chaos held at bay, a theme emphasized in tomb reliefs at Saqqara. On another level of symbolism, the pyramid form evoked the primal mound benben at the dawn of creation, a recurrent theme in ancient Egyptian cosmogony. This was represented first by megalithic benben stones, then obelisks, whose pyramidal tips were sheathed in glittering electrum an alloy of silver and gold , and finally pyramids, topped by electrum-covered pyramidion capstones, as seen in the Egyptian Museum.

Of the Seven Wonders of the ancient world, only the Pyramids of Giza have withstood the ravages of time. Resembling small triangles from afar and corrugated mountains as you approach, their gigantic mass can seem oddly two-dimensional when viewed from below. Far from being isolated in the desert as carefully angled photos suggest, they rise just beyond the outskirts of Giza City. During daytime, the tourist hordes dispel the mystique though the site is big enough to escape them , but at sunset, dawn and late at night their brooding majesty returns.

Their entrances are aligned with the Pole Star or rather, its position years ago ; the internal tomb chambers face west, the direction of the Land of the Dead; and the external funerary temples point eastwards towards the rising sun. Less well preserved are the causeways leading to the so-called valley temples, and various subsidiary pyramids and mastaba tombs.

Although the limestone scarp at the edge of the Western Desert provided an inexhaustible source of building material, finer stone for casing the pyramids was quarried at Tura across the river, or came from Aswan in Upper Egypt.

Blocks were quarried using wooden wedges which swelled when soaked, enlarging fissures and copper chisels, then transported on rafts to the pyramid site, where the final shaping and polishing occurred. Herodotus relates that a hundred thousand slaves took a decade to build the causeway and earthen ramps, and a further twenty years to raise the Great Pyramid of Cheops.

Archeologists now believe that, far from being slaves, most of the workforce were peasants paid in food for their three-month stint papyri enumerate the quantities of lentils, onions and leeks , while a few thousand skilled craftsmen were employed full time. One theory holds that a single ramp wound around the pyramid core, and was raised as it grew; when the capstone was in place, the casing was added from the top down and the ramp was reduced. Other ramps recently found led from the base of the pyramid to the quarry.

Whether or not the Ancient Egyptians deemed this work a religious obligation, the massive levies certainly demanded an effective bureaucracy. Pyramid-building therefore helped consolidate the state. By the time of the New Kingdom, other monumental symbols seemed appropriate.

Remembering the plundered pyramids, the rulers of the New Kingdom opted for hidden tombs in the Valley of the Kings. It originally stood m high and measured m along its base, but the removal of its casing stones has reduced these dimensions by three metres.

The pyramid is estimated to weigh six million tons and contain over 2,, blocks whose average weight is 2. This gigantic mass actually ensures its stability, since most of the stress is transmitted inwards towards its central core, or downwards into the underlying bedrock. It is thought to contain three main chambers: one in the bedrock and two in the superstructure. The rock is medium to coarse-grained showing, equigranular, hypidiomorphic, perthitic and piokilitic texture. The rock is composed mainly of potash feldspar microcline, orthoclase and perthite , quartz and plagioclase associated with considerable amounts of hornblende and biotite and accessory amount of muscovite, titanite, zircon and opaque minerals.

Alteration: the rock is affected by mild deformed and slightly alteration. Alteration products are clay minerals and sericite after potash feldspars and plagioclase. Hornblende and biotite are moderately altered to iron oxides. Quartz frequently shows curved boundaries and fractured, stretched and sutured due to mild deformation process. Opaque minerals: are minor amount, forming fine-grained dissemination in the rock.

Opaques show common association with biotite and hornblende. Significant amount of microfossils of different sizes and shapes are present in the matrix. Mineral composition: the rock is composed mainly of calcite as the essential component associated with minor amount of iron oxides and rare amounts of quartz, gypsum and opaque minerals. Iron oxides occur in considerable amount as fine-grained aggregates and also as patches stained some parts of the sample. The rock is highly stained by iron oxides Fig.

A somewhat higher porosity can be observed, which is due to the many open fossil interspaces. Further, a denser structure of the many small nummulites, discocyclinae, and other fossil remains is evident.

Microscopic photograph shows the backing Fossiliferous limestone Biomicrite blocks of Mykerinos pyramid. The rock is very fine to fine-grained. The rock is composed mainly of calcite as the essential component associated with minor amount of iron oxides and rare amounts of quartz, gypsum and opaque minerals.

Determination of the specific fossiliferious limestone weight; the real specific weight using Gibertini E42 scale and pycnometer and the bulk density using Gibertini E42 scale and caliper. Results are summarized in Table Five cylindrical specimens of backing limestone blocks were collected from the Khufu pyramid and verified to determine the characterization of pore media for this fossil limestone [ 29 ]. Note that: the distribution of the pore diameter of the basic sandstone blocks is, 10—20A 0.

Weathering is associated with structural properties, such as weak physical and mechanical properties of geometry, chemical composition, and the presence of soluble salts in porous systems of building stones and structural mortars that are considered the binding agents for building elements in the history of structures.

The durability of this limestone is moderate due to the weakness of binding material among the calcite grains. This moderate stone strength seriously affects the integrity of great hierarchical structures under constant and seismic loading conditions [ 34 , 35 ].

In order to maintain consistency, all the samples were cored to 50 mm in diameter using the same block of Fossilferious limestone at the same orientation. Of all the tests carried out, the test of the compressive strength of the stones is very important, as this value is used by structural design engineers to assess the stability and structural conditions.

The compressive strength is the maximum load per unit area that the stone can bear without crushing. A higher compressive strength indicates that the stone can withstand a higher crushing load. To determine the compressive strength, at least 5 specimens are tested in ASTM Each face must be perfectly flat and they must be parallel or perpendicular with each other. Faces must be smooth with no tool marks and there should be no nicks at the corners. Fifteen samples were equipped with electric strain gauges with a length of mm.

Vertical pressure was gradually increased pressure until failure. Table 11 shows the compressive strength results of the five backing limestone samples collected from the Cheops pyramid. The average elastic modulus obtained for the five tested cylinders is The results are shown in Table Figure 22 shows the uniaxial and triaxial compression testing set up.

The average elastic modulus obtained for the five cylinders tested is The results are given in Tables 13 and The results are given in Tables 15 and The low compressive strength of Mykerinos backing limestone specimens are due to its higher porosity which has be observed by mentioned thin sections. The high porosity may be due to the many open fossil interspaces. Further, a denser structure of the many small nummulites, discocyclinae, and other fossil remains is evident and reduced its stiffness and strength, see Fig.

The physical and mechanical properties of the construction materials of the three great pyramids are retreated because the area was subjected to intensive seasonal rainfall and evaporation in temperature Mediterranean climate conditions. The modeling of properties indicates a reliable relationship between the various visible pores and uniaxial compression force parameters that can be applied to predict and characterize limestone formations elsewhere.

Fifteen cylinders were tested to determine the average split tensile strength of the fossil limestone of the three great pyramids. The split tensile strength of the collected backing limestone specimens from of the great pyramid of Khufu is ranges from 1.

The limestone tensile strength of the collected backing limestone specimens from of the pyramid of Chephren pyramid ranges from 1. The limestone tensile strength of the collected backing limestone specimens collected from the pyramid of Mykerinos is ranges from 2. Tables 11 , 13 and 15 give details of test results. Fifteen cylinders were tested in single shear to determine the shear strength parameters of the filling limestone from the three great pyramids.

The obtained shear strength for the backing limestone from Cheops pyramids equal 1. The obtained shear strength for the backing limestone from Chephren pyramid equal 1. The obtained shear strength for the backing limestone from Mykerinos pyramid equal 0. Tables 11 , 13 and 15 summarize the results of shear test. Ultrasonic pulse velocity testing, mainly used to measure the sound velocity of the stones and hence the compressive strength of the stones. Measurement of longitudinal sound wave velocity can be an indication of the depth of crack observed on the surface.

The aim of the study here was to associate the velocity of sound with different mechanical properties [ 37 ]. P-wave velocities were measured by the Pundit CNS portable non-destructive ultrasonic indicator tester , which has two 65 kHz transducers transmitter and receiver. The backing limestone samples of the Cheops pyramid recorded low speed 3. Limestone samples from the Chephren pyramid recorded low speed 4. Figure 24 represent the test results. Modeling of the characteristics as shown in Fig.

In general, the rebound hammer is used to determine the quality of concrete and rock formations [ 38 , 39 ]. The Schmidt hammer method is one of the nondestructive testing techniques and is frequently adopted for evaluating the quality of in situ historic masonry structures. Whereas in this study, an attempt was made to assess the local compressive strength of limestone as a measure of the non-destructive test method. This approach requires extensive study and will be useful in the long term to test the heritage structures made of stones [ 40 , 41 ].

The Schmidt L-Type hammer of impact energy of 0. The hammer was transferred and 30 effects were performed on each sample. The hammer is forced against the surface of the stone block by the spring and the distance of rebound is measured on a scale.

The test surface was horizontal and vertical. Rebound Hammer test was carried out on selected structural backing limestone blocks. It serves as a tool to compare the strength of the existing structures. It gives a good indication on the limestone blocks surface hardness, which is reflective of the stone surface quality and strength.

The geochemical properties of the samples are medium and all are closely related. The values of the Schmidt hammer for the backing limestone blocks of the Khufu pyramid vary between RN 25 and 37; the results are given in Table The values of the Schmidt hammer for the backing limestone blocks of the Chephren pyramid vary between RN 24 and 36; the results are given in Table The values of the Schmidt hammer for the backing limestone blocks of the Mykerinos pyramid vary between RN 17 and 25; the results are given in Table The modeling of the characteristics as shown in Fig.

AIV was used as a standard test by which the aggregate impact strength was achieved. Fifteen tested limestone samples from the three pyramids are exposed to 15 hammer hits falling mm, at an interval of at least one second.

The shock strength of 15 hammer drops drops recorded very low values below 13 indicating poor limestone of the backing blocks of the Khufu pyramid, as shown in Table The impact strength of 15 hammer drops drops recorded very low values below 12 indicating poor limestone for the backing blocks of the Chephren Pyramid, as shown in Table The shock strength of 15 hammer drops drops recorded low values below 9 indicating poor limestone for the backing stone blocks of the Mykerinos pyramid, as shown in Table Table 17 summarizes the main physical characteristics of the joining mortars between backing limestone blocks from the three great pyramids.

For the Capillarity Coefficient of structural mortars, the samples were first submitted to the water absorption tests using the technique of capillary absorption by contact, which was developed and calibrated previously. The capillarity coefficient obtained by this test gives an idea of the compacity and consequently of the state of conservation of samples. Moreover, it is a non-destructive test introducing no changes to historic samples. The main esults are summarized in Table The pyramids complex suffered from different types of structural damage and construction materials decay and disintegration.

In recent years, the great pyramids of the year-old at Giza plateau, Cheops Khufu , Chephren Khafre , Mykerinos Menkaure and the Great Sphinx have been threatened by rising groundwater levels caused by water infiltration from the suburbs, Irrigation canals and mass urbanization surrounding Giza pyramids plateau GPP. The presence of building materials under investigation with great physical sensitivity to structural damage and weathering factors, especially dynamic procedures and high seismic events.

This study involved collection of intact stones and mortars samples without any damage but scattered on the floor; in situ testing of intact stones on the standing walls using non-destructive tests and carrying out laboratory testing of collected stone samples for assessment of strength characteristics. The multi-criteria analysis allowed the integration of several elements to map areas and zones at risk. The detailed analytical study proved that these pyramids complexes are built of natural building materials, for the three pyramids complex, the filling or backing stones blocks are Fossiliferous limestone had been quarried and transported from Giza quarries that lie only a couple of m south of the great pyramid, east of Khafre and south-east of the Mynkaure pyramid.

The rock-cut trench west and north of the Khafre pyramid yielded an enormous amount of stone material, which was incorporated directly into the core masonry. The outer casing stone blocks for Cheops, great pyramid are white fine limestone were quarried and transported from Mokkatam Formations in particular from Tura quarry.

The outer casing stone blocks for the Mykerinos, pyramid is granite was imported from Aswan quarry. The structural mortars joining the backing stone blocks of Cheops and Chephren pyramids are Gypsum mortars while is lime based mortar for the Mykerinos pyramid. The most of the casing stone blocks were destroyed and fell down in the A. C earthquake and were reused for the construction of many Coptic and Islamic historic buildings in Cairo.

The study presented a detailed view of the geochemical and engineering properties of the materials used in the construction of the three pyramids complex stones and structural mortars and the weathering and erosion factors that affect their durability and sustainability. The present study indicates the dependence of mechanical properties on the physical and petrochemical properties of the studied building materials.

Character modeling indicates a reliable relationship between different parameters. The study revealed the existence of an original hill of large volume under the two great pyramids.

The volume of this original hill is about Further site investigations are required to assess foundation details, bearing capacity and stability calculations for each section or segment of the pyramid complex. Concentrated strengthening and structural retrofitting intervention are therefore essential and necessary for preservation of the pyramids complex. The structural and non-structural measures recommended in this research will help decision makers and planners to develop effective site management strategies in the future, modify the modernization and structural rehabilitation of this unique archaeological site.

A perched groundwater table might exist in the elevated area toward the west and southwest. Great care must be taken regarding the impact of mass urbanization in the western Great Pyramids of Giza, which may affect the groundwater model in the region, see Fig.

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J Civil Eng Archit. We had an incredible time in Egypt although,at times, it was challenging. We felt absolutely fine there. The Step Pyramid of Pharaoh Djoser at Saqqara was the largest building of its time and illustrates the evolution from flat-roofed mastaba, to stacked mastabas, to pyramids.

It is m high and dates from around BC. The entire step pyramid complex is huge and includes temples, tombs and other structures, many can be entered today. The Red Pyramid, is the largest of the three Dahshur necropolis pyramids south of Cairo on the site of Ancient Memphis. It is m tall. The narrow passageway to the central tomb is over 61m deep. It may never have been used by its creator, the Old Kingdom Pharaoh Sneferu.

The broken or bent pyramid was also constructed by Pharoah Sneferu and was an earlier, failed , prototype. The Dahshur pyramids were closed to the public fr many years because of nearby army camps and activity. We had a driver and car arranged through our guest house owner and minder in Cairo.

For those of you not lucky to have a trusted contact , I would strongly recommend booking a tour with pick up from your Cairo accommodation and set price and itinerary.