In 1255 B.C. the great Egyptian pharaoh Ramses II built The Great Temple of Abu Simbel along the banks of the Nile. The temple, along with its twin, a smaller temple or his wife, Queen Nefertari, are a prime example of Ancient Egyptian engineering at its finest.
Gracing the entrance are four massive statues of Ramses II and smaller - yet still larger than life-size - statues of his wife, his children and people he conquered. It's an iconic work of art and a showcase for a Pharoah's giant ego. However, little would Ramses II know that 3200-plus years later, his temple would again become an engineering marvel for an entirely different reason.
In 1952, the new Egyptian government announced that the world's largest embankment dam would be built across the Nile. It would improve Egypt's economy, allowing the government to generate a stable supply of hydroelectric power, control the Nile's seasonal flooding better, and store water for irrigation more efficiently. However, the giant artificial reservoir created by the dam, or Lake Nasser, would submerge Abu Simbel when it reached its maximum level. The Egyptian government then asked for help from UNESCO to rescue the temples.
What followed is considered one of the most incredible feats of modern engineering. An international team dismantled the temple and turned it into the world's largest-ever 3D puzzle, reassembling it 65 meters higher from its original spot on the Nile river bank and almost 200 meters further inland.
After an almost four year period of intensive international fund-raising, the project began in earnest in 1963. Many countries submitted proposals like building an underwater aquarium to hold the submerged temple. This idea was quickly shelved since the temple is made out of sandstone, a very porous that would erode in the water in time. The sandstone also made it impossible to use explosives of any kind. Another idea was to cut the entire temple out in one go, but since they were carved straight into the cliff on its original site, it was impossible to lift all 250,000 tons safely.
In the end, it was Sweden that solved how to save the temples. They proposed that the whole temple and entrance facade be cut into 20-30 ton individual blocks using hand saws, pneumatic breakers, precise compressors and drills. Each cutting line had to be planned meticulously per block, so it wasn't visible when the temple was reassembled.
The temple's cardinal directions had to be precisely the same as when it was in its location, so the sun's rays would still shine on the statues inside the temple. Each block was secured with steel reinforcement bars and reassembled like a giant jigsaw puzzle. After a gruelling five years, the project was completed in 1968, and in 1979, Abu Simbel became part of UNESCO's World Heritage List.
Today, Abu Simbel is visited by thousands of tourists daily and is the 2nd most visited ancient site in Egypt.