How the Seven Wonders of the Ancient World Work

Out of the rolling sands of Egypt rise mysterious, conical forms: the pyramids. Across Egypt, there are 80 of various sizes. But it's the greatest of the pyramids, and the mightiest of the Great Pyramids, the Pyramid of Khufu, which ranks among the seven wonders.

The Greeks called Khufu Cheops in their accounts. It stands alongside Giza's other two Great Pyramids: Menkaure and Khafre. Nearby, the Sphinx watches guard. Khufu's staggering height of 480 feet (146.3 meters) held reign as the world's tallest structure until the Eiffel Tower surpassed it in 1889.

The Pyramid of Khufu is not only the oldest of the ancient wonders -- it's the only one still standing. Situated on the Giza Plateau, near the city of Cairo, it was built during King Khufu's reign from 2589 to 2566 B.C. The pyramid is made of more than 2,300,000 limestone and granite blocks and weighs approximately 6.5 million tons (5.89 million metric tons). Its sloping sides pay homage to the sun god, Ra, symbolizing his rays of light. These slopes rise at 51 degrees and have an area of 5.5 acres [source: Great Pyramid of Giza Research Association]. Each block fits tightly together -- less than a fiftieth of an inch separates them. Its four sides are situated at each of the cardinal directions, which proves how closely the ancient Egyptians were attuned to astronomy.

Khufu was originally covered with a limestone casing. It may be hard to visualize a smooth, glistening pyramid because we are familiar with its rough, weather-beaten appearance. In the 14th century, earthquakes struck Egypt, toppling temples and snapping bridges. Khufu's limestone casing was removed and repurposed for repairs. As a result, the pyramid was lowered in height by five percent, reduced to a still-mighty height of 456 feet (139 meters) [source: History Channel].

Khufu's interior is no less impressive than its façade. Intended as a tomb for the king and his queen, its primary purpose seems to be housing their bodies and storing the goods they need for the afterlife. Compact shafts and dark passageways weave serpentine paths through chambers and dead-end at impassable tunnels and secret rooms. For centuries, pyramidologists, archaeologists who study pyramids, have been excavating Khufu. But their work has been challenging. Egyptians made Khufu almost impossible to navigate to deter thieves and protect the tombs and treasures within. Some rooms and chambers are sealed with slabs of stone. Other rooms seem to exist for no reason except as deterrents to would-be robbers. A room in the queen's chamber, for instance, contains nothing but sand. More empty chambers serve as relief chambers, absorbing the stress of the pyramid's weight [source: BBC]. Still others are simply undiscovered or impassable.

We don't know for sure how the pyramids were built. Most scholars agree that construction provided employment for peasants when the Nile River's annual flooding kept them from tending their farms.

They've always been a popular tourist destination, and Egyptians as well as ardent admirers of Khufu resent the pyramid's relegation to mere "runner-up" on the new list of world wonders.

Next, we'll learn about a wonder that may not have even existed: the Hanging Gardens of Babylon.

If they existed, the Hanging Gardens of Babylon would be the second oldest of the ancient wonders. Built in the 6th century, the gardens are long gone. Some scholars argue that the reason there's no record of them is precisely because they were gardens -- plants and flowers are living things that eventually die. Even if the structure on which the gardens were affixed remains, it could very well be in unrecognizable ruins.

We'll start with the most popular theories about the gardens. They were likely located by the Euphrates River in what is now modern-day Iraq. The gardens didn't actually hang: They draped over the sides of terraces on a brick structure. Some accounts of the gardens claim that they grew as high as 75 feet (22.86 meters) in the air and that people could walk beneath them. Accounts from the classical writer Diodorus Siculus describe that the brick walls were 22 feet (6.7 meters) thick and 400 feet (121 meters) wide. And Philo wrote that there were several strata of flora and many levels of irrigation.

The gardens wouldn't have been the only grand sight in Babylon. This ancient city was filled with shining palaces and sturdy ziggurats. Even the city gates were adorned with carvings and gleamed with glazed bricks [source: Smithsonian]. But in a desert country as dry as Iraq, canopying fronds and blooms would have been an awesome sight to see.

If Babylon's buildings boasted of its great wealth, then the gardens would've demonstrated the engineering skills of their architect. It's no small feat to keep plants thriving in the desert, but to transport water to flowers perched atop a nearly five-story building is a monstrous challenge. The gardens would have relied on the Euphrates as their irrigation source, and the water would likely have been transported through a pumping system made of reeds and stone and stored in a massive holding tank. From the tank, a shaduf (a manually-operated water-lifting device) would have delivered water to the plants.

According to legend, King Nebuchadnezzar built the gardens for his wife, Amytis. Amytis was a princess from Media, a region of Iran near the Caspian Sea. Nebuchadnezzar is said to have built the gardens for her as a reminder of her homeland. But it's strange that Nebuchadnezzar, who recorded his many accomplishments in cuneiform, a type of ancient writing used in record-keeping, didn't mention the gardens.

This has led some scholars to theorize that the gardens were actually built by an Assyrian queen or even by Sennacherib, the ruler of Nineveh.

Today, our knowledge of the Hanging Gardens of Babylon comes from interpretations of ancient accounts and artists' renderings of the wonder.

In the next section, we'll travel to Turkey to explore the Temple of Artemis at Ephesus.

Ephesus was the largest city in Asia Minor, which is modern-day Turkey. It was a Greek port and known as a city of magic.

The Temple of Artemis was originally built in 550 B.C. by King Croesus of Lydia [source: Princeton]. In terms of appearances, it resembled the classical Greek temple: a stoic rectangular structure with mighty columns. The temple measured 350 by 180 feet (106.68 by 54.86 meters). From the outside, its most striking feature was its more than 100 marble columns. Built in the Ionic architectural style, the columns were decorated with sculptural reliefs at their bases and rosettes in their capitals. Two rows of columns stretched across the front of the temple, standing about 21 feet (6.4 meters) apart and extending from the front to the back of the temple at 17 feet (5.18 meters) apart. Lion head-shaped gutters added another dimension of style, as well as looming statues of Amazons that framed a door in the temple's pediment, or base. The door in the pediment -- along with two windows -- was intended for Artemis' use.

Inside the temple was perhaps the most fascinating sight of all: the statue of Artemis. It was built from gold, silver, ebony and other stones.

The Artemis of the Temple of Ephesus looked nothing like the goddess of the hunt. Her likeness was based on the Anatolian Earth goddess Cybele. She wore a dress carved with images of animals and a shawl made of bees [source: PBS]. The most interesting aspect of the statue was the rows of bulbs that hung from her body. Scholars debate what, exactly, these were: breasts or testicles. The theory that they're breasts corresponds to her representation of fertility, but the likelihood that they're sacrificial bull testicles is even greater. Worshippers would have sacrificed bulls on the goddess's behalf, and some accounts state that the cult of Cybele, after whom the statue was modeled, was lead by priests who castrated themselves to emulate her [source: Ward].

Artemis was not only the patron goddess of the temple but also a beacon of comfort for her city. Escaped slaves slept in her shadow and pilgrims traveled long distances to see Artemis. The statue was so popular that the local economy was largely supported by the temple's tourists and the souvenir replicas they bought.

On July 21, 356 B.C., a pyromaniac named Herostratus burned the temple to the ground, hoping to achieve infamy. According to legend, Artemis couldn't save her burning temple because she was present at the birth of Alexander the Great [source: Hillman]. The temple was later rebuilt, but we're not sure of the exact date this was accomplished. Alexander had offered to fund its reconstruction but wanted his name inscribed on the temple -- that offer was delicately rebuffed. When it was reconstructed, it was built on an even grander scale with a taller pediment and of solid marble.

In 262 A.D., marauding Goths raided the temple, and in the fifth century A.D., its remaining marble was used to rebuild the city. After a series of earthquakes, its ruins settled into the marshlands of the Cayster River [source: History Channel]. The archaeologist John Turtle Wood discovered the temple's remains in 1860. Today, one marble column resides in the British Museum.

Next, we'll learn about another formidable statue: the Statue of Zeus.

Zeus, king of the Greek gods, was embodied in larger-than-life form in the Temple at Olympia in ancient Greece. Olympia was a sacred site and the location of the Olympic games. The temple represented Greek architecture's fascination with proportion. It was 68 feet (20.7 meters) tall with 72 Doric columns. The pediment and metopes (eaves beneath the roof) were sculpted, and imposing bronze doors opened to reveal the wonder housed within.

Written accounts described that temple visitors shuddered and cowered under the shadow of Zeus' mighty statue. The Greek artist Phidias was commissioned to create this likeness of the god. His work began in 450 B.C. and concluded eight years later with a legendary masterpiece of ivory and gold. Ivory was an unusual choice for sculptural media, but it might have been a natural choice for the king of the gods, given its rarity [source: Times]. Phidias sculpted Zeus at Olympia sitting ramrod-straight in a bejeweled throne. The statue measured 50 feet (12 meters) high, and observers noted that if Zeus were to rise from his throne, his head would likely burst through the ceiling.

Perhaps the most remarkable thing about the statue was Zeus' expression. His eyes appeared to penetrate even the most hardened souls to elicit piety [source: Smithsonian]. He held an object in each hand: in the right, a statue of Nike (goddess of victory) and in the left, a scepter adorned with an eagle. Zeus' throne was carved with images from mythology of gods, demigods and other heroes.

Legends say that Phidias asked for Zeus' blessing when he finished his sculpture. In response, a bolt of lightning struck the temple.

There is some debate about the statue's reign as master of the temple. While some sources claim that the statue was placed in the temple around 450 B.C., others estimate the date 430 B.C. With Christianity's encroaching threat to the ancient gods, some Greeks paid to have their beloved statue removed to safety in Constantinople, which is modern-day Istanbul. Christians shut down the temple in 391 A.D., and the statue was guaranteed safe-keeping until either 462 or 475 A.D., when it was burned in a fire.

We know quite a bit about the statue. Just as United States' currency depicts important monuments and faces, ancient Greek coins featured the prominent statue of Zeus. This currency gives us details about his appearance, and we can judge how strong an attraction the statue had to tourists based on how far they carried coins from Olympia. And in 1950, a major archaeological breakthrough came when Dr. Emil Kunze and his team found the remains of Phidias' workshop next to the temple's ruins. Using evidence from inch-long to 18-inch-long terra cotta and iron molds, Kunze was able to reconstruct what the statue might have looked like and how it might have been built. Kunze theorized that the statue was built from thin plates of gold stretched across wood model.

From the immortal god to the immortalization of an ordinary king, our exploration of the ancient wonders takes us back to Turkey next.

Many of the wonders fit into some architectural or artistic style. The Mausoleum of Halicarnassus boldly defies categorization. Its style was what some might call "busy" or "too much." There's a reason for that. While the mausoleum was intended as a memorial, after its commissioner died, it became a showcase for competing artists to exhibit their greatest work. To that end, the mausoleum became a mishmash of marble sculpture, carving and columns.

The word mausoleum comes from King Mausolus, the Persian king of Caria, for whom the temple was built. He ruled in the fourth century A.D. in Halicarnassus, now modern-day Bodrum, Turkey. Mausolus held an unremarkable reign. He married his sister, Artemisia, who loved him very deeply. She was heartbroken by his death, and one legend says that she went so far as to mix his ashes with water and drink them to mourn Mausolus [source: History Channel].

To honor her brother and husband, Artemisia commissioned a grand mausoleum for his remains. She elected the architect Pythius to design it and hired four sculptors to embellish it (that's one sculptor per side -- Pythius sculpted the crowning sculpture for the apex of the mausoleum): Scopas, Bryaxis, Leochares and Timotheus [source: Princeton].

A hilltop with a view of the city and the bay was chosen for the mausoleum's location. Work began in 353 B.C. The mausoleum towered 140 feet (45 meters) in the air with a base 99 feet (32 meters) high; a 24-step, 22 feet (7 meters) tall pyramid; and a crowning statue of 19 feet (6 meters). The ancient historian Pliny wrote that the perimeter of the mausoleum was 440 feet (134 meters) [source: Princeton]. More modern excavations led by a Danish team from 1966-1977 revealed that it was probably 100 by 120 feet (30 by 36 meters) with 36 supporting columns.

The queen never saw her husband's monument completed. She died just two years after Mausolus and was buried with him. However, work continued on the mausoleum because the artists wanted to complete their projects. These included Pythius' sculpture of Mausolus and Artemisia in a chariot led by four houses; friezes depicting the Greek war with the Amazons; various races and wars between Lapiths (the people of ancient Thessaly) and centaurs (mythical creatures that are half-human, half-horse); as well as other sculptures. Today, some remnants of these sculptures and friezes are in the British Museum.

In the 1400s, earthquakes shook the foundations of the mausoleum, and it slowly crumbled. Around 1494, the Knights of St. John of Malta used the temple's remains to strengthen their castle. They also burned marble columns to create lime mortar.

Excavations of the mausoleum turned up some very interesting things. In 1522, Charles Guichard found Mausolus and Artemisia's burial chamber. It contained an alabaster sarcophagus -- but mysteriously, no bodies. The Danish team that explored the site in the late 1960s found remains of eggs, doves, oxen and sheep that were probably offered to the king and queen as food for the afterlife.

In the next section, we'll travel back to Greece to examine the giant Colossus.

The Colossus of Rhodes in ancient Greece was said to be the only statue larger than the mighty Zeus at Olympia. But this statue didn't last as long as Zeus -- at least not vertically.

In the third century, the Greek island of Rhodes was confronted by angry Macedonians. They wanted the Rhodians' help waging war against Ptolemy I in ancient Egypt. But the Rhodians didn't want to get involved in the conflict. They resisted the Macedonians, and the warriors eventually relented. The Macedonians left behind all of their supplies and equipment.

The Rhodians were so thankful for their safety that they decided to honor their patron god -- Helios, the sun god -- with a statue. They sold the Macedonians' cast-off goods to earn money for it. Around 294 B.C, the sculptor Chares of Lindos began work on the colossus. Using bronze, iron and stones for building materials, it took him 12 years to complete the statue. It measured nearly 110 feet (33 meters) high when finished -- that's about the height of a 15-story building [source: Hillman].

No one knows for sure what the colossus looked like or where it was located on the island. Judging from written accounts, scholars have proposed that it was a standing figure holding a torch in one hand. And some accounts testify that its face was modeled after Alexander the Great's [source: Smithsonian]. Legends say that he stood over the harbor, one leg on either side forming a majestic tunnel.

While there are plenty of accounts and illustrations that support this theory (some suspiciously from the Middle Ages, centuries after the statue had been destroyed), it's unlikely that the colossus would have stood over the harbor. For one thing, Chares didn't have the knowledge, materials or skills to support the weight of a statue in this position. Even more telling, the bustling port city of Rhodes wouldn't have been able to support its people with the harbor out of commission during the statue's erection. Instead, the statue was probably sculpted in the classical Greek style with both legs planted solidly under his shoulders and some sort of base for support. Furthermore, the colossus was likely located inland near the center of town [source: Princeton].

The colossus stood strong for 53 years until an earthquake struck Rhodes in 225 B.C. The colossus broke at its knees, and when it toppled over, it crushed several houses and buildings in its wake. When the Rhodians considered rebuilding the colossus, an oracle, or message from the gods, advised them not to. For almost four centuries, the colossus lay prostrate on the ground. Pliny wrote that it was still a wonder to see in this condition. Tourists would try to wrap their arms around the colossus' thumb, but it was too big to grasp [source: Smithsonian].

In 653 A.D., invading Arabs sold the toppled Colossus for scrap metal. Its legacy lives on in the style of a famous statue created by Frederic Bartholdi: the Statue of Liberty.

For our last stop on the tour of ancient wonders, we island-hop back to where we started: Egypt. Last, we'll learn about the Lighthouse of Alexandria.

Scholars have called the Lighthouse of Alexandria the only practical wonder since it served a utilitarian purpose. We have plenty of information about it, but some are conflicting accounts. The story of the lighthouse begins with Alexander the Great.

According to Plutarch, Alexander had a dream in which he was told to seek the small island of Pharos, located just off the coast of ancient Egypt. He chose Ptolemy I Soter, one of his army's generals, to settle the island. Ptolemy decided that Pharos needed something to identify it, both symbolically and literally -- its coast was difficult to navigate.

Some scholars credit the idea for the lighthouse to Ptolemy and others attribute it to the mouseion, a governmental brain trust [source: Smithsonian]. Around 285 B.C., construction began. A man named Sostrates of Knidos was instrumental to the process. By some accounts, he was the financial backer for the project -- the lighthouse cost about 800 talents, bars of silver, equal to roughly three million dollars [source: Princeton]. Other accounts identify him as the lighthouse's architect.

Even if we can't be sure of the lighthouse's architect, we are certain of its architecture. It was built with marble and mortar and composed of three stories. The first level was rectangular, the second octagonal and the third cylindrical. Perched atop the third story was a statue -- either of Zeus or Poseidon, god of the sea. Records from Moorish travelers in the tenth century A.D. say that the lighthouse was 300 cubits high, which converts to about 450 feet (137 meters).

A spiral ramp led to its entrance. Carts and workhorses could be led up to the first level to the hundreds of storage rooms. To access the upper levels, one had to use the spiral staircase. Dumbwaiters lifted supplies to the highest tower.

Ships could supposedly see the lighthouse from a hundred miles away [source: PharosLighthouse.org]. During the day, light was reflected from the sun with a concave metal disc; at night, light came from a bonfire, fueled by firewood or dried animal dung. The lighthouse survived through more than 22 earthquakes before it came toppling down in 1303 [source: Clement]. The people of Pharos loved their lighthouse dearly -- it was a source of power and revenue for the island. They attempted to repair and restore the lighthouse throughout the ninth and thirteenth centuries when it became clear that it could no longer be saved.

Today, a fort stands on its site. The identity of Pharos became so enmeshed with the lighthouse that the lighthouse became alternately known as the Pharos of Alexandria. "Pharos" is also the root of the word "lighthouse" in several languages. And our knowledge of the lighthouse continues to grow after a 1994 archaeological scuba expedition found sunken remnants of the lighthouse.

To learn more about the lighthouse, the other ancient wonders and the new wonders of the world, explore the links on the next pages.

There were only seven wonders on the original list, and each successive list has stuck to that perfect Pythagorean digit. But there have been quiet murmurings of an eighth wonder. Fleetwood Mac's song "Seven Wonders" hints that an unrequited love is the elusive eighth wonder while Hollywood would have us believe that the eighth wonder is really André the Giant or King Kong. Modern architects are apt to call towering buildings like the Empire State Building or the Palm Islands of Dubai the eighth wonder.