BEIJING, April 28 (Xinhua) - Xi'an, the provincial capital of northwest China's Shaanxi province, opened a major international horticultural expo on Thursday as it seeks to promote its history as one of China's ancient capitals.

This marks the third time for a Chinese mainland city to host a horticultural event of this scale. Over the past 12 years, two similar expos have been held in the cities of Kunming and Shenyang.

Visitors to the Xi'an International Horticultural Exposition can feast their eyes on abundant flowers and diverse gardening styles from the country's different regions, as well as get a taste of Xi'an's cultural and historical legacy.

The expo is taking place on Guangyun Lake in the city's eastern Baqiao district, which used to be one of ancient China's key seaports. Historical records show that during the Tianbao Period of the Tang Dynasty (742-756 AD), when Xi'an was known as Chang'an, Chinese emperor Tangxuangzong organized a large-scale international trade exposition in the city. Organizers claim that this was one of the first international expositions in history.

"Over a thousand years later, Guangyun Lake welcomes another grand gathering, the World Horticultural Exposition, which has continued this time-honored tradition from Tang's Chang'an to the modern Xi'an," said Jiang Zehui, chairman of the China Flower Association.

Shaanxi Province vice governor Yao Yinliang said the province was one of the first regions of China to be seen by the rest of the world, adding that the famous "Silk Road" started in the city of Chang'an, which served as ancient China's capital for more than 1,200 years and 13 dynasties.

An opening ceremony was held Thursday morning near the Chang'an Tower, a Chinese-style pagoda that serves as one of the city's landmarks.

The design of the tower was based upon the characteristics of pagodas built in the Tang Dynasty (618-907 AD), a period during which China made great cultural, political and economic achievements.

The 13-story tower is home to famed works of art, such as samples of glazed pottery from the Tang Dynasty. The first floor of the tower houses a four-horse bronze chariot unearthed near the Tomb of Qingshihuang, the first great emperor of China.

The expo also demonstrates a wide variety of gardening styles from both China and abroad. The expo's European Avenue sports white stone sculptures of angels and a "dancing" water fountain, which are integrated into the area's neatly groomed shrubbery and flowers, giving viewers a glimpse of a typical European-style garden.

In the expo's Taipei Garden, white moth orchids are in full bloom, while seas of red and yellow tulips add bright splashes of color to the park.

In the Swedish Garden, after passing through a group of birch trees, visitors can reach a green patch of grassland after passing through a small forest of birch trees, the simplicity of which provides for a good place for guests to rest.

In a unique twist, a pavilion created by the Beijing-headquartered International Network for Bamboo and Rattan demonstrates how these two plants can be used to make reliable, solid furniture such as chairs and tables. Bamboo keyboards and even decorative soccer balls are also on display there.

Cheng Bin, vice general manager of the Xi'an International Horticultural Park Co., said the site of the expo park was a landfill just ten years ago.

"But now, we are turning this wasteland into an ecological city, and we hope that by hosting the horticultural expo, the city of Xi'an will learn a more balanced way of living in which people and nature coexist in harmony," said Cheng, who also participated in last year's Shanghai World Expo.

Expo organizers said a total of 109 cities and organizations are participating in the event, which is expected to attract 12 million visitors until it concludes on October 22.