The Cross Of Changes: Wonders of the World

Great Pyramid of Giza

The Great Pyramid of Giza, also called Khufu's Pyramid or the Pyramid of Khufu, and Pyramid of Cheops, is the oldest and largest of the three pyramids in the Giza Necropolis bordering what is now Cairo, Egypt, and is the only remaining member of the Seven Wonders of the Ancient World. It is believed the pyramid was built as a tomb for Fourth dynasty Egyptian King Khufu (Cheops in Greek) and constructed over a 20 year period concluding around 2560 BC. The Great Pyramid was the tallest man-made structure in the world for over 3,800 years. Originally the Great Pyramid was covered by casing stones that formed a smooth outer surface, and what is seen today is the underlying core structure. Some of the casing stones that once covered the structure can still be seen around the base. There have been varying scientific and alternative theories regarding the Great Pyramid's construction techniques. Most accepted construction theories are based on the idea that it was built by moving huge stones from a quarry and dragging and lifting them into place.

There are three known chambers inside the Great Pyramid. The lowest chamber is cut into the bedrock upon which the pyramid was built and was unfinished. The so-called Queen's Chamber and King's Chamber are higher up within the pyramid structure. The Great Pyramid of Giza is the main part of a complex setting of buildings that included two mortuary temples in honor of Khufu (one close to the pyramid and one near the Nile), three smaller pyramids for Khufu's wives, an even smaller "satellite" pyramid, a raised causeway connecting the two temples, and small mastaba tombs surrounding the pyramid for nobles.

It is believed the pyramid was built as a tomb for Fourth dynasty Egyptian pharaoh Khufu and constructed over a 14 to 20 year period concluding around 2560 BC. Khufu's vizier, Hemon, or Hemiunu, is believed by some to be the architect of the Great Pyramid. It is thought that, at construction, the Great Pyramid was 280 Egyptian royal cubits tall, 146.6 meters, (480.97 feet) but with erosion and the loss of its pyramidion, its current height is 138.8 m. Each base side was 440 royal cubits, with each royal cubit measuring 0.524 meters. The total mass of the pyramid is estimated at 5.9 million tonnes. The volume, including an internal hillock, is believed to be roughly 2,500,000 cubic meters. Based on these estimates building this in 20 years would involve installing aproximatly 800 tonnes of stone every day. Manetho gives Khufu a reign of 65 years this would enable him to build the pyramid by installing aproximatly 250 tonnes of stone per day. The first precision measurements of the pyramid were done by Egyptologist Sir Flinders Petrie in 1880–82 and published as The Pyramids and Temples of Gizeh. Almost all reports are based on his measurements. Petrie found the pyramid is oriented 4' west of North and the second pyramid is similarly oriented. Many of the casing stones and interior chamber blocks of the great pyramid were fit together with extremely high precision. Based on measurements taken on the north eastern casing stones, the mean opening of the joints are only 1/50th of an inch wide.

The pyramid remained the tallest man-made structure in the world for over 3,800 years, unsurpassed until the 160 meter tall spire of Lincoln Cathedral was completed c. 1300. The accuracy of the pyramid's workmanship is such that the four sides of the base have a mean error of only 58 millimeter in length, and 1 minute in angle from a perfect square. The base is horizontal and flat to within 15 mm. The sides of the square are closely aligned to the four cardinal compass points (within 3 minutes of arc based on true north not magnetic north). The completed design dimensions, as suggested by Petrie's survey and later studies, are estimated to have originally been 280 cubits in height by 4 × 440 cubits at its base. These proportions equate to 2 to an accuracy of better than 0.05% which some Egyptologists consider to have been the result of deliberate design proportion. Verner wrote, "We can conclude that although the ancient Egyptians could not precisely define the value of π, in practise they used it". Petrie, author of ‘The Pyramids and Temples of Gizeh', who was the first accurate surveyor of Giza and the excavator and surveyor of the Pyramid of Meidum, concluded: "but these relations of areas and of circular ratio are so systematic that we should grant that they were in the builders design" Earlier in the chapter he wrote more specifically, that: “We conclude therefore that the approximation of 7 to 22 as the ratio of diameter to circumference was recognised.

For more info : http://en.wikipedia.org/wiki/Great_Pyramid_of_Giza

Colosseum

The Colosseum or Roman Coliseum, originally the Flavian Amphitheatre is an elliptical amphitheatre in the center of the city of Rome, Italy, the largest ever built in the Roman Empire. It is one of the greatest works of Roman architecture and Roman engineering.

Occupying a site just east of the Roman Forum, its construction started between 70 and 72 AD under the emperor Vespasian and was completed in 80 AD under Titus, with further modifications being made during Domitian's reign (81–96). The name "Amphitheatrum Flavium" derives from both Vespasian's and Titus's family name (Flavius, from the gens Flavia).

Originally capable of seating around 50,000 spectators, the Colosseum was used for gladiatorial contests and public spectacles. As well as the gladiatorial games, other public spectacles were held there, such as mock sea battles, animal hunts, executions, re-enactments of famous battles, and dramas based on Classical mythology. The building ceased to be used for entertainment in the early medieval era. It was later reused for such purposes as housing, workshops, quarters for a religious order, a fortress, a quarry, and a Christian shrine.

Although in the 21st century it is in a ruined condition due to damage caused by earthquakes and stone-robbers, the Colosseum is now an iconic symbol of Imperial Rome. It is one of Rome's most popular tourist attractions and still has close connections with the Roman Catholic Church, as each Good Friday the Pope leads a torchlit "Way of the Cross" procession to the amphitheatre.

For more info: http://en.wikipedia.org/wiki/Colosseum

Taj Mahal

The Taj Mahal, is a mausoleum located in Agra, India, that was built under Mughal Emperor Shah Jahan in memory of his favorite wife, Mumtaz Mahal.

The Taj Mahal (also "the Taj") is considered the fines example of Mughal architecture, a style that combines elements from Persian, Turkish, Indian, and Islamic architectural styles. In 1983, the Taj Mahal became a UNESCO World Heritage Site and was cited as "the jewel of Muslim art in India and one of the universally admired masterpieces of the world's heritage."

While the white domed marble and tile mausoleum is most familiar, Taj Mahal is an integrated symmetric complex of structures that was completed around 1648. Ustad Ahmad Lahauri is generally considered to be the principal designer of the Taj Mahal.

For more info : http://en.wikipedia.org/wiki/Taj_Mahal

Great Wall of China

The Great Wall of China is a series of stone and earthen fortifications in China, built, rebuilt, and maintained between the 6th century BC and the 16th century to protect the northern borders of the Chinese Empire from Xiongnu attacks during the rule of successive dynasties. Several walls, referred to as the Great Wall of China, were built since the 5th century BC. The most famous is the wall built between 220–200 BC by the first Emperor of China, Qin Shi Huang; little of it remains; it was much farther north than the current wall, which was built during the Ming Dynasty.

The Great Wall stretches over approximately 6,400 km (4,000 miles) from Shanhaiguan in the east to Lop Nur in the west, along an arc that roughly delineates the southern edge of Inner Mongolia, but stretches to over 6,700 km (4,160 miles) in total. At its peak, the Ming Wall was guarded by more than one million men. It has been estimated that somewhere in the range of 2 to 3 million Chinese died as part of the centuries-long project of building the wall.

For more info : http://en.wikipedia.org/wiki/Great_Wall_of_China

Leaning Tower of Pisa

The Leaning Tower of Pisa (Italian: Torre pendente di Pisa) or simply The Tower of Pisa (La Torre di Pisa) is the campanile, or freestanding bell tower, of the cathedral of the Italian city of Pisa. It is situated behind the cathedral and is the third oldest structure in Pisa's Piazza del Duomo (Cathedral Square) after the cathedral and the baptistry.

Although intended to stand vertically, the tower began leaning to the southeast soon after the onset of construction in 1173 due to a poorly laid foundation and loose substrate that has allowed the foundation to shift direction. The tower presently leans to the southwest.

The height of the tower is 55.86 m (183.27 ft) from the ground on the lowest side and 56.70 m (186.02 ft) on the highest side. The width of the walls at the base is 4.09 m (13.42 ft) and at the top 2.48 m (8.14 ft). Its weight is estimated at 14,500 metric tons (16,000 short tons). The tower has 296 or 294 steps; the seventh floor has two fewer steps on the north-facing staircase. The tower leans at an angle of 3.97 degrees. This means that the top of the tower is 3.9 metres (12 ft 10 in) from where it would stand if the tower were perfectly vertical.

For more info : http://en.wikipedia.org/wiki/Leaning_Tower_of_Pisa

Niagara Falls

The Niagara Falls are massive waterfalls on the Niagara River, straddling the international border separating the Canadian province of Ontario and the U.S. state of New York. The falls are 17 miles (27 km) north-northwest of Buffalo, New York, 75 miles (120 km) south-southeast of Toronto, Ontario, between the twin cities of Niagara Falls, Ontario, and Niagara Falls, New York.

Niagara Falls is composed of two major sections separated by Goat Island: Horseshoe Falls, on the Canadian side of the border and American Falls on the United States side. The smaller Bridal Veil Falls also is located on the American side, separated from the main falls by Luna Island. Niagara Falls were formed when glaciers receded at the end of the Wisconsin glaciation (the last ice age), and water from the newly-formed Great Lakes carved a path through the Niagara Escarpment en route to the Atlantic Ocean. While not exceptionally high, the Niagara Falls are very wide. More than six million cubic feet (168,000 m³) of water falls over the crest line every minute in high flow, and almost 4 million cubic feet (110,000 m³) on average. It is the most powerful waterfall in North America.
The Niagara Falls are renowned both for their beauty and as a valuable source of hydroelectric power. Managing the balance between recreational, commercial, and industrial uses has been a challenge for the stewards of the falls since the 1800s.

For more info : http://en.wikipedia.org/wiki/Niagara_Falls

The Kaaba

The Kaaba is a cuboidal building in Mecca, Saudi Arabia, and is the most sacred site in Islam. The building is at least a thousand years old, but according to Islamic tradition dates back to the time of Abraham (Ibrahim). It is towards the Kaaba which all Muslims around the world face during prayer, no matter where they are on Earth.

The building has a mosque built around it, the al-Masjid al-Haram. One of the Five Pillars of Islam is that every Muslim who is able to do so, must travel to Mecca at least once in their lifetime to perform the Hajj pilgrimage, which includes a series of rituals. Multiple parts of the Hajj require that the pilgrims walk several times around the Kaaba in a counter-clockwise direction. This circumambulation, the Tawaf, is also performed by pilgrims during the Umrah (lesser pilgrimage). However, the most dramatic times are during the Hajj, when two million pilgrims simultaneously gather to circle the building on the same day.

For more info : http://en.wikipedia.org/wiki/Kaaba

Bermuda Triangle

The Bermuda Triangle, also known as the Devil's Triangle, is a region of the northwestern Atlantic Ocean in which a number of aircraft and surface vessels have disappeared or are alleged to have disappeared. Some people have claimed that these disappearances fall beyond the boundaries of human error or acts of nature. Popular culture has attributed some of these disappearances to the paranormal, a suspension of the laws of physics, or activity by extraterrestrial beings. Though a substantial body of documentation exists showing numerous incidents to have been inaccurately reported or embellished by later authors, and numerous official agencies have gone on record as stating the number and nature of disappearances to be similar to any other area of ocean, many have remained unexplained despite considerable investigation.