8 Wonders of the Ancient World
Take a tour of history’s greatest human-made landmarks
The Pyramids of Giza and the Sphinx
Built between 2589 and 2504 BCE, the three Pyramids of Giza served as extravagant tombs for ancient Egyptian pharaohs, large enough to house everything they would need in the afterlife. The largest, constructed for the Pharaoh Khufu, consists of 6.5 million tons of stone, some in blocks as heavy as nine tons each. However, no one quite knows how they were moved into position. One theory is that a system of sledges, rollers and levers were used to haul the blocks up a slope that was increased in height as the pyramid grew. Meanwhile, the Sphinx, which stands close to the pyramids, was carved out of the limestone bedrock of the Giza Plateau.
Banaue Rice Terraces
More than 2,000 years ago, the indigenous people of Ifugao in the Philippines came up with an ingenious method for farming on steep terrain. With no tools available, they carved a series of terraces out of the mountain, bordering them with walls of mud and stone. They then harvested water from the forests on top of the mountain, flooding the individual fields so that rice could grow. This method of farming and sustaining the terraces has since been passed down through the generations and is still practised today.
The Hanging Gardens of Babylon
According to ancient sources, Babylonian King Nebuchadnezzar II built a luscious hanging garden for his wife in 600 BCE because she was homesick for the beautiful vegetation of her native Media. But although vivid descriptions of the gardens were given, no physical evidence has been found, leading many to believe it never existed. However, a more recent search has discovered that the hanging gardens may not have been in Babylon at all, but were instead built a century earlier in the city of Ninevah by King Sennacherib. It is thought they were planted on a series of terraces and an Archimedes’ screw device was used to douse them with 300 tons of water a day.
Half-built and half-carved from the pink sandstone that inspired its colourful nickname, Petra was established as the capital of the Nabataean Kingdom in 400 BCE. As a busy trading hub, it was once home to around 20,000 people, but getting access to water was difficult in the middle of the desert. The Nabataeans solved this problem by constructing an elaborate water management system featuring cisterns, reservoirs and dams that conserved seasonal rains. They chiselled their buildings out of the cliffs by carving steps into the surrounding rock, providing them with safe ledges to work from, and ensured important monuments aligned with the sunrise on winter solstice.
Pharos of Alexandria
In need of a method for guiding trade ships into Alexandria’s busy harbour, the Egyptian ruler Ptolemy Soter commissioned the construction of a lighthouse in around 280 BCE. Designed by Greek architect Sostratus of Cnidus, it consisted of three levels, each built from a light-coloured stone and reinforced with molten lead. The lower square level supported an eight-sided structure, on top of which sat a cylindrical section containing a curved mirror that reflected the light from a fire into a beam. The finished lighthouse is thought to have been about 135 metres tall, but was reduced to rubble by two earthquakes in the 14th century.
The Great Wall of China
Although the first sections of border walls had been built in the 8th century BCE, it wasn’t until 220 BCE that Emperor Qin ordered for them to be joined up as a protective barrier. He set 300,000 soldiers plus many more peasants and prisoners to work constructing the wall from stone, soil, wood and even sticky rice, which helped hold the bricks together. The materials were transported to the site by hand or using wheelbarrows, ropes and animals.
In 80 BCE, after less than ten years of construction, Rome’s enormous entertainment venue was completed. A pioneering feat of enginering, it would go on to host bloody gladiator battles, re-enactments and executions for four centuries. The innovative four-tiered design of multiple vaulted arches provided plenty of support without adding excess weight and enabled more than 100,000 slaves to build it in simple, standardised parts. The recent invention of concrete also added strength, helping it hold crowds of more than 50,000 people at a time.
In the Wiltshire countryside of England stands one of the most iconic and oldest human-made landmarks in the world. Built over thousands of years, Stonehenge is the only surviving stone circle of its kind and has become a site of incredible archaeological importance. Although it has revealed a lot about certain practices of the past, the structure is still shrouded in mystery, mainly because we still can’t be sure what it was built for. The most popular theory is that it was a prehistoric temple, as the stones are precisely aligned with the movements of the Sun across the sky, which has special religious significance. What we do know is that its construction began in 3100 BCE, when a large circular ditch was dug using tools made from antlers. Around this time, the site was used for burials; in fact it’s the largest late Neolithic cemetery in the UK. In 2500 BCE, the stones were erected, having been worked into shape and smoothed using sarsen and flint hammerstones, and a few hundred years later were rearranged into their final position. Over the years many of the stones have toppled or been removed, leaving Stonehenge in its current state.
This article was originally published in How It Works issue 100, written by Jo Stass
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