The Egyptian pharaoh Khufu built the Great Pyramid in about 2560 B.C. to serve as his tomb. The Great Pyramid is the largest of three Pyramids at Giza, bordering modern-day Cairo. Although weathering has caused the structure to stand a few feet shorter today, the pyramid was about 480 feet (145 meters) high when it was first built. It is the only remaining ancient wonder.

In contrast to the pyramids, the colossus was the shortest lived of the seven wonders of the ancient world. Completed in 282 B.C. after taking 12 years to build, the Colossus of Rhodes was felled by an earthquake that snapped the statue off at the knees a mere 56 years later. The towering figure—made of stone and iron with an outer skin of bronze—represented the Greek sun god Helios, the island's patron god. It looked out from Mandráki Harbor on the Mediterranean island of Ródos (Rhodes), although it is no longer believed to have straddled the harbor entrance as often shown in illustrations. The Colossus stood about 110 feet (33 meters) tall, making it the tallest known statue of the ancient world. It was erected to celebrate the unification of the island's three city-states, which successfully resisted a long siege by the Antigonids of Macedonia.

Constructed on the small island of Pharos between 285 and 247 B.C. Its estimated height was 384 feet (117 meters)—equivalent to a modern 40-story. The lighthouse was operated using fire at night and polished bronze mirrors that reflected the sun during the day. It's said the light could be seen for more than 35 miles (50 kilometers) out to sea. The huge structure towered over the Mediterranean coast for more than 1,500 years before being seriously damaged by earthquakes in A.D. 1303 and 1323.

The massive gold statue of the king of the Greek gods was built in honor of the original Olympic games, which began in the ancient city of Olympia. The statue, completed by the classical sculptor Phidias around 432 B.C., sat on a jewel-encrusted wooden throne inside a temple overlooking the city. The 40-foot-tall (12-meter-tall) figure held a scepter in one hand and a small statue of the goddess of victory, Nike, in the other—both made from ivory and precious metals. The temple was closed when the Olympics were banned as a pagan practice in A.D. 391, after Christianity became the official religion of the Roman Empire. The statue was eventually destroyed, although historians debate whether it perished with the temple or was moved to Constantinople (now Istanbul) in Turkey and burned in a fire.

The hanging gardens are said to have stood on the banks of the Euphrates River in modern-day Iraq, although there's some doubt as to whether they ever really existed. The Babylonian king Nebuchadnezzar II supposedly created the terraced gardens around 600 B.C. at his royal palace in the Mesopotamian desert. It is said the gardens were made to please the king's wife, who missed the lush greenery of her homeland in the Medes, in what is now northern Iran.

The famous tomb at Halicarnassus—now the city of Bodrum—was built between 370 and 350 B.C. for King Mausolus of Caria, a region in the southwest of modern Turkey. Legend says that the king's grieving wife Artemisia II had the tomb constructed as a memorial to their love. Mausolus was a satrap, or governor, in the Persian Empire, and his fabled tomb is the source of the word "mausoleum." The structure measured 120 feet (40 meters) long and 140 feet (45 meters) tall.

The tomb was most admired for its architectural beauty and splendor. The central burial chamber was decorated in gold, while the exterior was adorned with ornate stone friezes and sculptures created by four Greek artists. The mausoleum stood intact until the early 15th century, when Christian Crusaders dismantled it for building material for a new castle. Some of the sculptures and frieze sections survived and can be seen today at the British Museum in London, England.

The great marble temple dedicated to the Greek goddess Artemis was completed around 550 B.C. at Ephesus, near the modern-day town of Selçuk in Turkey. In addition to its 120 columns, each standing 60 feet (20 meters) high, the temple was said to have held many exquisite artworks, including bronze statues of the Amazons, a mythical race of female warriors. A man named Herostratus reportedly burned down the temple in 356 B.C. in an attempt to immortalize his name. After being restored, the temple was destroyed by the Goths in A.D. 262 and again by the Christians in A.D. 401 on the orders of Saint John Chrysostom, then archbishop of Constantinople (Istanbul).