The Seven Wonders
Die first reference to the idea of a list of seven wonders is found in History of Herodotus as long ago as the 5th century BC. His list comprised of the pyramids, the Hanging Gardens, and the Babylon among others. Callimachus of Cyrene (305BC-240BC), Chief Librarian of the Alexandria Museum, wrote “A Collection of Wonders around the World”. When the surviving list of the Seven Wonders of the World was compiled during the Middle Ages, the structures listed were believed to be the greatest examples of architecture in the world. The historian and poet Antipater compiled a list of seven structures that is close to the list that remains today except that his list included the Walls of Babylon instead of the Lighthouse of Alexandria. The list of the Seven Wonders of the World include: The Great Pyramid of Giza, The Colossus of Rhodes, The lighthouse at Alexandria, The Hanging Gardens of Babylon, Statue of Zeus at Olympia, The Mausoleum at Halicarnassus and Temple of Artemis (Diana) at Ephesus.
In 2001 an initiative was started by the Swiss Corporation New 7 Wonders Foundation to choose the New Seven Wonders of the World from a selection of 200 existing monuments. Twenty-one finalists were announced on January 1, 2006. The pyramid of Giza was named as an honorary Candidate. The results were announced on July 7, 2007. These were the new Seven Wonders of the World. The list included the Great wall of China, The Taj Mahal, Machu Picchu, The lost city of Petra, Chichen Itza, The statue of Christ the Redeemer and the Roman Colosseum.
Apart from this there exist several lists based on the same theme. There are the seven wonders of the underwater world, which lists all the natural underwater formations around the world. Then the seven natural wonders of the world which lists all the formations with nature as an architect and the seven wonders of the man-made world which pay a tribute to engineering and the creativity of man.