When Mao Zedong stood atop the Gate of Heavenly Peace 60 years ago today to proclaim the establishment of the People's Republic of China, he looked out on a Tiananmen Square packed with a cheering crowd of 300,000. Behind him was the Forbidden City, from where Ming and Qing emperors had ruled the country for hundreds of years. If Mao had looked far beyond the crowd to the city his People's Liberation Army had occupied nine months beforehand, he would have seen a nearly collapsed city wall, shabby houses and dirt roads. Today, President Hu Jintao , the fourth generation communist leader, will stand at about the same spot Mao stood and see a similar-sized crowd marching past Tiananmen to celebrate the 60th anniversary. But the distant background will be starkly different. The old city wall has long been torn down to build Beijing's second ring road and the old, shabby, low-rise houses have been replaced by high-rise residential buildings, priced at about 30,000 yuan a square metre. If Hu glances to the east, he will see the 330-metre-high Tower III of the China World Trade Centre, Beijing's highest building, which will host some of the world's leading companies when completed later this year. The contrast around Tiananmen reflects how much the capital has been transformed in the past 60 years, especially after China decided to adopt the reform and opening up policies in late 1970s, but it is just the tip of the iceberg. In the 1950s, when Mao saw the need to flatten the old city wall to make way for a road, which later became the second ring road, Beijing had around 10,000 vehicles. On September 12, when Beijing's 188-kilometre-long sixth ring road was completed, Beijing had about 4 million vehicles, with the number increasing by about 12,000 new vehicles a week. Statistics released by Beijing Bureau of Statistics early last month showed the capital's annual gross domestic product had reached 1.05 trillion yuan by the end of last year, 1,329 times bigger than its 790 million yuan GDP in 1952. The average income of Beijing residents jumped from 360 yuan in 1978 to 16,460 yuan last year. On a tour of the city's Dashilan area in November, Mayor Guo Jinlong said it was important to balance economic growth and heritage preservation. 'Beijing is a city full of famous historic heritage, so it's very important that we properly protect those treasures in the old city area,' he said, adding that the government should play a leading role in the process. Cheng Guoqing , a worker with Beijing Shougang Group, is one of 12 grass-roots lecturers selected by the municipal government to share their own stories about the transformation of Beijing over the past six decades with other residents. Cheng's father began working for Shougang in 1939 and Cheng himself started work at the factory in 1959. 'We worked like crazy to build Shougang from a garage-like factory into one of the largest steel makers in the country in the past 60 years, and the growth of Shougang is a living proof of how the city of Beijing has managed to rise from scratch into one of the best cities in the world,' Cheng told listeners at a library in the city's Chaoyang district last month. Ironically though, the Shougang story, no matter how glorious it might sound, has now lost its geographical connection with the capital. Shougang was relocated last year to the Hebei city of Tangshan to improve Beijing's air quality for the Olympic Games. It speaks of the environmental costs, among other challenges, the city faces after decades of breakneck development. Great changes in Beijing come with great moments. Some, such as the Beijing Olympic Games, were the pride of the nation, and the kind of achievement state and city leaders do not mind reminding the world about. However, people around the world have also witnessed darker periods in the city's recent history, such as when People's Liberation Army soldiers and armoured vehicles rolled into Tiananmen Square in the summer of 1989 to crush the pro-democracy student movement. Discussion of that event is still a political taboo on the mainland. The famous Beijing-born writer Liu Heng once described the city as a sponge, which sucked up everything, good or bad, to make itself bigger. He said people could hold their own opinions on Beijing, but the reality was the city would not be the unique place it is today if anything was taken away from its recent history.