Taj tops the list...
Taj Mahal, India: The white marble-domed mausoleum in Agra combines Indian, Persian and Islamic styles and was built by a 17th century Mogul emperor for his favorite wife, who died in childbirth.
Great Wall of China: The 4,160-mile barricade running from east to west is the world's longest man-made structure. The construction of the wall took place over hundreds of years, beginning in the seventh century B.C.
Petra, Jordan: This ancient city in southwestern Jordan, built on a terrace around Wadi Musa, or Valley of Moses, was the capital of the Arab kingdom of the Nabateans. The city is famous for water tunnels and stone structures carved in the rock.
Christ Redeemer Statue, Brazil: The outstretched arms of the 125-foot statue of the Christ the Redeemer overlooks Rio de Janeiro from atop 2,343-foot Mount Corcovado.
Machu Picchu, Peru: Built by the Incan Empire in the 15th century, Machu Picchu's walls, palaces, temples and dwellings are perched in the clouds at 8,000 feet above sea level in the Andes.
Pyramid at Chichen Itza, Mexico: This pyramid was part of a sacred site in an important Mayan center on Mexico's Yucatan peninsula. Built according to the solar calendar, shadows at the fall and spring equinoxes are said to look like a snake crawling down the steps, similar to the carved serpent at the top.
Colosseum, Italy: The 50,000-seat amphitheater in Rome was inaugurated in A.D. 80 and served as the backdrop for thousands of gladiators who dueled to the death.