After 20 years of digging, Austrian archeologists say they've determined the design of a Mesopotamian ziggurat built by King Nebuchadnezzar 2,500 years ago.
The temple tower consisted of seven terraces built of millions of mud bricks and rose 231 feet, the scientists say. It probably was similar to the many ziggurats built by Nebuchadnezzar, the ruler who ordered the destruction of the ancient Jewish temple in Jerusalem, they add.
The temple of Borsippa, 75 miles south of Baghdad, was constructed atop the ruins of a smaller tower from the second millennium B.C. Nebuchadnezzar's temple was dedicated to Nabu, the god of science and learning in Mesopotamia and the king's protector.
Wilfrid Allinger-Csollich of the University of Innsbruck said that of all the temple towers built during Nebuchadnezzar's 40-year reign, the Borsippa ziggurat has best survived the ravages of time.
The Austrians removed thousands of tons of debris from the mound that gradually built up around the tower over the ages and uncovered most of the ziggurat's remains, which still rise to 172 feet. The work revealed the tower's exact dimensions, Allinger-Csollich said.
"We did not use high-tech, but rudimentary means. We just counted the number of bricks," he said.
The square bricks used by Nebuchadnezzar had standard dimensions--13 1/4 inches on each side and 3 1/4 inches in depth. The Austrians used mechanical shovels to reach the foundation, which they measured at 297 by 297 feet.
More than 1 million fired bricks were used for the first level's 3.3-foot-tall outer wall, Allinger-Csollich said.
Given the Borsippa tower's height of 231 feet, "you can imagine how many more millions [of bricks] were needed in the construction of the outer walls of other stages," he said.
The builders filled the inside of each level with tens of millions of unfired bricks held in place with cedar beams brought from Lebanon.
The Austrians determined the tower had three staircases and are in the process of calculating how many steps each had.
Their picture of the temple's exterior is almost complete. The first two levels were covered with bitumen and were black. The third, fourth and fifth were decorated with blue-glazed bricks and possibly adorned with bulls and lions.
The sixth and seventh terraces, close to the sanctuary, were wholly made of mud brick.
"For cultic purposes the Mesopotamians thought mud to be the purest of substances," said Helga Trenkwalder, leader of the seven-member Austrian team. "On top was Nabu's residence, with rooms for servants and priests and wings for his wife, Tachmitum, his children and daughters. It must have looked really fantastic."
Trenkwalder said Borsippa, being the residence of Nabu, was the center of learning in Mesopotamia.
"There must have been a big library of cuneiform tablets here, but we have missed it so far," she said.
Among her finds are several tablets and a foundation stone with inscriptions detailing why and how Nebuchadnezzar constructed the tower in Borsippa.
One text says the king wanted the Borsippa tower built on the same design as that of the Tower of Babel, of which only the foundation survives in Babylon 7 miles to the north.
Another text quotes Nebuchadnezzar as declaring that Nabu's tower should reach the skies and be no less in grandeur than that of Babel, which was dedicated to the god Marduk.
Allinger-Csollich said the team's evidence from texts and excavations shows a tower of "greater dimensions than ours existed in Babylon."
Iraq has another impressive ziggurat in Ur, which was built about 2500 B.C. But Nawal al-Mutawali of the Iraq Museum said Borsippa's remains are "greater, higher and more elegant."
Dony Youkhanna, assistant director of Iraq's Antiquities Department, said the government is trying to persuade the United Nations to declare Borsippa a world heritage site to give it international protection.