The official list of the seven Wonders of the Ancient World was compiled in the Middle Ages, after most of the seven wonders had toppled. Only the Great Pyramid at Giza has survived.
Wonders of the ancient world were mentioned first by the historian Herodotus and then by Callimachus, librarian at Alexandria. In about 140 B.C. a Greek writer you probably haven't heard of, Antipater of Sidon, wrote a poem listing ancient wonders. This is Antipater's main claim to fame. His list is not identical with the list you'll find here.
The list is in chronological order of when the structure was built.
Michal Charvat. http://egypt.travel-photo.org/cairo/pyramids-in-giza-after-closing-hours.html
The Great Pyramid of Giza, in Egypt, was build around 2650-2500 B.C. The oldest of the 7 wonders and the only one still standing, the pyramid was built for the Pharaoh Khufu of the 4th Egyptian dynasty
The Hanging Gardens of Babylon were created around c. 600 B.C. if they ever existed. The hanging gardens of Babylon were destroyed sometime after the 1st century B.C., probably by earthquake.
The statue of Artemis and her temple at Ephesus
were built around 550 B.C. The temple of Artemis was deliberately burned down by Herostratus in an attempt to gain fame in 356 B.C. supposedly when Alexander the Great was born.
The Statue of Zeus at Olympia was built around 435 B.C. by the great sculptor Pheidias. It succumbed to fire in the fifth or sixth century A.D.
The statue was located in the largest Doric temple of its time, the 5th century B.C. limestone Temple of Zeus at Olympia, the focal point for the ancient Olympics. It may have been built in time for the Olympics of 460 or 456, under the direction of the architect Libon.
"Technical Observations on the Sculptures from the Temple of Zeus at Olympia," by John G. Younger and Paul Rehak; Hesperia: The Journal of the American School of Classical Studies at Athens, Vol. 78,No. 1 (Jan. - Mar., 2009), pp. 41-105.
The Mausoleum of Halicarnassus was commissioned for Mausolus by his wife Artemisia and finished around 350 B.C. It was destroyed by earthquake in the 14th century, but some of its ornaments are in the British Museum.
The Colossus of Rhodes was built around 292-280 B.C. It was destroyed by earthquake in 225 making the Colossus of Rhodes the shortest lasting of all the 7 wonders. The statue was of the god Helios.
The Pharos lighthouse was erected by about 270 B.C. The lighthouse in the harbor of Alexandria stood until 14th century earthquakes destroyed it. In 1994 archaeologist found blocks believed to be part of the lighthouse.