Scholars disagree about the first person to compile the list of the seven wonders, such as the Colossus of Rhodes shown here. See more of these marvels from the Great Pyramid of Giza to the Hanging Gardens of Babylon on the following pages.
The Colossus lighthouse was built on the Greek island of Rhodes, circa 250 B.C. The statue, which stood 110 feet (33.5 meters) high, was a depiction of the sun god Helios. No one is sure exactly what the Colossus looked like.
Despite artists' fancy over the ages, it's unlikely the statue straddled the harbor, as requisite skill and materials to support such a structure didn't exist yet. Like several of the wonders to come, the Colossus was destroyed by an earthquake in 225 BC.
The ancient city of Babylon was the site of the Hanging Gardens of Babylon, as well as the Tower of Babel, grand palaces and ziggurats.
If they were still standing, the Hanging Gardens would be the second oldest of the ancient wonders. Here you can see what is thought to be the ruined substructure of the site.
The Hanging Gardens of Babylon had multiple levels filled with all sorts of plant life, their branches and blooms spilling over the walls. The challenge of irrigating a five-story building was made easier by the garden's location near the Euphrates, but it still took some clever engineering.
In 1983, Iraqi president Saddam Hussein began reconstruction at Babylon. Hussein's plans for Babylon included a new modern palace and even plans for a cable car. The work remains incomplete.
The Mausoleum at Halicarnassus built between 353 and 350 B.C. for Mausolus, a satrap in the Persian Empire. The building was constructed by an architect and four sculptors -- each used one side of the structure to showcase his work.
The mausoleum was destroyed by earthquakes in the 15th century, its materials eventually becoming part of other structures. You can still visit the ruins in present-day Bodrum, Turkey.
The Temple of Artemis also lies in modern-day Turkey, in what was a Greek port town known as Ephesus. King Croesus of Lydia had the colonnaded temple built in 550 B.C. It was burned to the ground in 356 BC, reconstructed, and met its final end in the fifth century after raids and earthquakes.
The 100-plus columns of the Temple of Artemis featured relief-sculpted bases and rosettes at the capitals, typical of Ionic architecture. Inside was a statue of Artemis made of gold, silver, ebony and other stones.
The lighthouse on the island of Pharos guided ships into the port of Alexandria, Egypt. It was the tallest known lighthouse of its kind.
Construction began on the lighthouse around 285 B.C. Travelers in the tenth century A.D. estimated its height at 300 cubits, which converts to about 450 feet (137 meters).
The lighthouse stood until it was ruined by earthquake damage in the 14th century. The next stop is on the other side of the Mediterranean in Greece.
These crumbling columns in a field of daisies at Olympia once supported a mighty temple during the time of the first Olympic Games.
The central temple was the work of the architect Libon of Elis. Here's a view of an Olympic Games awards ceremony at Olympia.
The highlight of the temple complex was a statue of Zeus, 50 feet (12 meters) high, made of ivory and gold by the Greek sculptor Phidias. Byzantine Emperor Theodosius II ordered that the statue and temple be destroyed, and the ruins were devoured later by earthquakes until their rediscovery in the 18th century.
The Great Pyramid of Giza is both the oldest of the seven wonders and the only one that still stands. It was constructed as a tomb for Pharoah Khufu, completed around 2560 BC. The pyramid was originally covered in a smooth, glistening limestone casing.
Here, the Great Sphinx at Giza, one of the largest statues on Earth, stands in front of the Great Pyramid. The Great Pyramid was the tallest man-made feature on earth for almost 4,000 years.
The construction date for the Sphinx remains under dispute, but that just adds to the mystery that draws legions of visitors to the site every year. How do the seven wonders compare to modern landmarks?
From left to right: the Temple of Artemis, the Lighthouse of Alexandria, the Leaning Tower, St. Peter's Basilica, the Great Pyramid of Giza, the Eiffel Tower, Sears Tower, the Hanging Gardens of Babylon, the Mausoleum of Halicarnassus, and the CN Tower. Learn more about those ancient architectural feats in How the Seven Wonders of the Ancient World Work.