China's National Pavilion Day provided one of the highlights on Friday of Expo 2010 with a ceremony to mark the 61st anniversary of the republic.

The Shanghai ceremony was one of many held across the country to mark National Day.

In Beijing, President Hu Jintao and Premier Wen Jiabao laid flowers on Friday morning at the Monument to the People's Heroes on Tian'anmen Square to pay their respects to those who sacrificed their lives for the country.

In Shanghai, top legislator Wu Bangguo, international leaders and celebrities marked China National Pavilion Day at the Expo.

In his address to the ceremony, Wu said China has every reason to believe that Expo will be remembered as a successful and unforgettable event.

"Although it will end in one month's time, the spirit of progress, innovation, harmony and common prosperity advocated by the Expo will long endure," he said.

Vicente Loscertales, secretary-general of the Bureau of International Exhibitions (BIE), said China had made history and set new standards for World Expos including the largest number of participants and visitors, as well as the biggest Expo site.

"Since China was awarded Expo 2010 by the BIE, it has demonstrated a genuine commitment," he said.

China has risen to meet the global challenge of improving the quality of urban life by making it the theme of its Expo, Loscertales added.

In the past five months, the Expo gathered participants from 246 countries, regions, and international organizations. Almost 60 million visitors came to the Expo from home and abroad.

Expo, which started on May 1 and runs until Oct 31, showcases the latest in urban-living concepts in pavilions from practically every country and many international organizations, cities and big corporations.

Yet, the highlight of the Expo site on Friday was the China Pavilion, an embodiment of the nation's power and pride. Each visitor to the hall was given a gift bag including a broach and souvenir postcard.

David Ziskind, a visitor from Israel, said he was impressed by the pavilion's gigantic structure, which at 69 meters tall is triple the height of nearby pavilions.

"It represents a powerful country, celebrating its economic success," he said.

On Thursday evening, the country's top leaders, including President Hu, attended a Beijing reception to mark the 61st anniversary of the founding of the People's Republic of China.

"China's development will neither harm anyone nor pose a threat to anyone," Premier Wen said at the reception. The argument that a strong country is bound to seek hegemony does not apply to China, he added.

This is the last year for implementing China's 11th Five-Year Plan (2006-10). Premier Wen said the country is at a "new historical starting point", and the coming five years will be crucial to China's efforts in building a prosperous society.

On Friday, more than 150,000 people attended the flag-raising ceremony on Tian'anmen Square, regarded as an honor on the National Day by the Chinese.

The National Day saw millions of people on the move as they traveled to see friends and families during the holidays.

However, bad weather and accidents on Friday morning caused delays to many.

The Beijing-Tibet Expressway had been jammed since early morning on Friday due to a traffic accident and a 20-kilometer jam had developed by mid-morning.

Rail traffic was especially heavy in and out of Beijing.

The number of people who left the capital by train reached a peak of 280,000 on Thursday, the Ministry of Railways said.