An exhibition that features the largest number of terra cotta warriors ever to travel to the United States for a single show kicked off here on Tuesday.

The exhibition, "Terra Cotta Warriors: Guardians of China's First Emperor," will officially open to public on Thursday at the National Geographic Museum, which is the final venue of the exhibition's four-city U.S. tour, following Los Angeles, Atlanta and Houston.

Open through March 31, 2010, the exhibition includes 15 terra cotta figures from the tomb of China's First Emperor, Qin Shihuang, who ruled from 221 B.C. to 210 B.C.

"The First Emperor's magnificent terra cotta army is one of the great wonders of the ancient world," said Terry Garcia, National Geographic's executive vice president for Mission Programs, in a statement.

"Visitors to the National Geographic Museum will have the rare opportunity to experience one of the greatest archaeological discoveries of the 20th century as they stand face-to-face with the terra cotta warriors," he said.

Xie Feng, minister of the Chinese Embassy to the United States, said at Tuesday's opening ceremony and media preview that there are three unprecedented features about the exhibition.

Apart from the unprecedented number of displays, more than 50 media organizations covered the opening of this exhibition, which is the widest media representation in all exhibitions in Washington, D.C., he said.

He also said that a record number of 96,000 tickets have been sold online in advance.

According to Shaanxi museum officials, the exhibition showcases 15 life-size terra cotta figures, including nine warriors, and 100 sets of objects, including weapons, stone armor, coins, jade ornaments, roof tiles and decorative bricks, and a bronze crane and swan.

Among the display, there are 20 "Level 1" artifacts — China's highest possible ranking in terms of rarity and importance.

In support of the exhibition, the museum has published a companion book, Terra Cotta Warriors: Guardians of China's First Emperor, and made a documentary, "The Real Dragon Emperor," featuring the latest archaeological research and imaging techniques that take viewers inside the massive tomb of Qin Shihuang.