Archeologists find 5,500 year old plaza in Peru

LIMA, Feb 25 (Reuters) - A circular plaza built 5,500 years ago has been discovered in Peru, and archeologists involved in the dig said Monday carbon dating shows it is one of the oldest structures ever found in the Americas.

A team of Peruvian and German archeologists uncovered the plaza, which was hidden beneath another piece of architecture at the ruins known as Sechin Bajo, in Casma, 229 miles north of Lima, the capital.

"It's an impressive find, the scientific and archeology communities are very happy," said Cesar Perez, the scientist at Peru's National Institute of Culture who supervised the project. "This could redesign the history of the country."

Prior to the discovery at Sechin Bajo, archeologists considered the ancient Peruvian citadel of Caral to be one of the oldest in the Western Hemisphere, at about 5,000 years.

Scientists say Caral, located a few hours drive from Sechin Bajo, was one of six places in the world -- along with Mesopotamia, Egypt, China, India and Mesoamerica -- where humans started living in cities five thousand years ago.

"The dating done by the German archeologists puts it at about 5,500 years, but other parts could be older depending on what else is found," Perez said.

Earlier finds near Sechin Bajo had been dated at 3,600 years.

"They had a highly-developed understanding of architecture and construction. This can clearly be seen in the fact that the materials they used survived for so long," Peter Fuchs, one of the archeologists, told the El Comercio newspaper.

The social gathering space that Fuchs and his colleagues found was built with rocks and adobe bricks.

Hundreds of archeological sites cover Peru, and many ruins were built by cultures that preceded the powerful Incan empire, which reached its peak in the 16th century, just before Spanish conquerors arrived in what is now Peru. (Reporting by Marco Aquino, writing by Terry Wade, editing by Vicki Allen)