The Yangtze joins the Blue Danube. Traditional Chinese-style Tang blouses are refitted into ballet dresses. Artists of different colors sing and dance on the same stage.

The Shanghai World Expo opened Friday night with artistic performances, fireworks and high technologies that epitomized 159 years of Expo history.

Thousands of people watched the gala live at the futuristic, UFO-shaped Shanghai Expo Cultural Center, a centerpiece facility at the Expo Park, while thousands more enjoyed fireworks, lights and fountains on the waterfront promenade, the Bund.

Across China, millions shared Shanghai's celebration in front of their TVs.

The indoor performances starred China's piano prodigy Lang Lang, famous for his dramatic countenance and gestures, who played the New Shanghai Concerto, the event's theme music.

The presence of international stars, including Andrea Bocelli, Shinji Tanimura and Maori dancers, turned the stage truly international.

More than 100 ballet dancers danced to the "Song of the Yangtze," a classic ode to China's "mother river". Johann Strauss's "Blue Danube" joined the Yangtze and east met west.

The virtual tides of the "Blue Danube" projected on the center stage then turned into a time tunnel, where images of earlier World Expos flew by, represented by landmark inventions, including electric lamps, silk, a motorcar, a steamer, a maglev train and a satellite.

The first World Expo ever in a developing country, the Shanghai event would lead new lifestyles, promote harmony between people and nature as well as the overall development of humanity, Vice Premier Wang Qishan said in his address at the opening ceremony.

The 184-day event, running until Oct. 31, has drawn participation by an unprecedented 189 countries and 57 international organizations and is expected to host an estimated 70 million visitors.

SHANGHAI GREETS WORLD

China's largest city, at the mouth of the Yangtze, began to evolve into the metropolis it is today in the 19th Century, when the British established a concession there after the first Opium War in 1842.

The city was known as the "Paris of the East" in the 1920s and 1930s for its beautiful buildings and prevalence of Western vogue and lifestyles.

After New China was founded in 1949, Shanghai was for decades the country's top manufacturing base, with "made in Shanghai" snacks, clothing and light industrial products coveted by most Chinese people.

It was also among the first to benefit from China's economic reforms that began in the late 1970s. The country's first stock exchange opened there in 1990.

Today, the city of 18 million people is China's financial hub with towering skyscrapers, a meeting point of migrant laborers, bankers, artists and businesspeople from around the globe, with more transnational marriages than elsewhere in China.

The Shanghai organizers, proud of their native culture yet eager to reach out to the world, adorned the international gathering with local elements. "We're gonna see the world together ala nong," sang Siedah Garrett and Jonathan Buck, two American singers of the theme song "Better city, better life".

In Shanghai dialect, incomprehensible to most other Chinese, "ala" stands for "we" and "nong" means "you".

Messages of welcome were conveyed in the songs, dances, the dazzling light and fireworks display on the Huangpu River that showed smiling faces, rainbows, as well as text messages of "EXPO" and "harmony", and the friendly smiles of the Shanghainese.

"We've been looking forward to this," said Zhang Wei, a volunteer at the Expo's media center. He is among 72,000 volunteers at the Expo Park, a 5.28-square-km area straddling the Huangpu River.

About 2 million others are offering voluntary services across the city.

A HARMONIOUS GATHERING

The opening ceremony, produced by a team of Chinese and foreign directors, was designed to be simple, but with highlights, and warm, but not extravagant.

"China is taking the World Expo stage in a concise and modest manner," said Teng Junjie, chief director for the production of indoor performances.

While earlier expos showcased great inventions, recent events are also tackling the challenges brought by progress, including pollution, traffic congestion and energy deficiency.

As president of the International Exhibitions Bureau Jean-Pierre Lafon put it, the Shanghai event is expected to "contribute to a social awakening so that our cities may become more sustainable, fairer, safer and harmonious."

Amid global concerns over pollution and climate change, and in an effort to live up to its theme of "Better city, Better life", Shanghai organizers have made 2,000 VIP seats in the Expo Cultural Center out of deserted milk packages.

Handbags and tissues were made of recycled paper, while low-energy consuming LED screens and acoustic devices were used at the opening ceremony.

"Chinese elements are found throughout the ceremony," said Liu Wenguo, an official with the Bureau of the Shanghai World Expo Coordination, citing fireworks, drums and the Butterfly Lovers, a Romeo and Juliet-style romance.

"These have brought the essence of Chinese culture to the global audience, and achieved the combination of Chinese and Western value systems."

David Atkins, who headed the production team for the outdoor ceremony, said the opening was a "harmonious gathering" and celebration of the city, its future and history.