WHEN people think about Tiananmen, different things come to mind. For most Chinese, it is a Beijing landmark, the heart of China. For Yan Shujun, Tiananmen is an addiction.

"I'm obsessed with collecting items related to Tiananmen," says Yan.

The 44-year-old colonel in the People's Liberation Army stays up till 3am almost every night, scanning auction Websites for all things connected with Tiananmen.

Collecting started as a hobby in the early 1990s, but Yan now has amassed 20,000 items, including photos, documents, books, envelopes, notebooks, postcards, marriage certificates, diplomas, food coupons, train tickets, match boxes, cigarette packages, vases - anything that bears the image of Tiananmen or any relevance to Tiananmen.

A fixture at Beijing's antiques markets, Yan spends most weekends hunting for Tiananmen-related things. Every time he appears, the shop owners call out, "The Tiananmen guy is here."

To obtain some rare items that he longs for, Yan frequents auctions across the nation, and sometimes he travels long distances to buy from other collectors.

Yan has exhausted almost all his time and earnings - his salary and royalties from 32 books he compiled and stories published in literary magazines - to add to his Tiananmen collection.

Tiananmen, literally meaning "gate of heavenly peace," was first built during the Ming Dynasty (1368-1644) in 1420. It was the entrance to the Forbidden City, which served as the imperial palace for almost five centuries. Tiananmen lies on the northern edge of Tiananmen Square.

"My obsession with Tiananmen can be traced back to 1971," Yan recalls.

Back then, Yan was six and had just started in elementary school. It was at school that he first heard of Chairman Mao Zedong and Tiananmen. "Our first text was 'Long Live Chairman Mao' and, our teacher told us that Chairman Mao declared the founding of new China at Tiananmen in Beijing."

From a village in Zunhua County, in the northern city of Tangshan, Hebei Province, Yan had no idea what those words really meant. He recalls, "I just thought to myself, where is Tiananmen? Where is Beijing? When can I see Chairman Mao?"

On July 28, 1976, an earthquake hit Tangshan while Yan was sleeping. His father saved him, but the earthquake killed 240,000 people and flattened more than 90 percent of the city's homes, including Yan's.

A few days later, food and supplies were air-dropped by the PLA and the head of the county encouraged the survivors to work hard for reconstruction.

"Chairman Mao sent the PLA to give us food. If we do a good job, we can go to Beijing and we can see Chairman Mao," Yan still remembers the village chief saying. That reinforced the idea of Beijing, Tiananmen and Chairman Mao in his mind.

Dream fulfilled

But Yan's dream was shattered three months later when Mao passed away on September 9, 1976. When the news reached his village, Yan recalls, "I felt so lost. The person I wanted to see the most had left us. I didn't know what to do."

Like his peers, Yan wept. But he told himself, "Mao is gone. Yet, Tiananmen is still there, the portrait of Chairman Mao on Tiananmen is still there."

Not until October 6, 1988, when he was 24 did Yan get to see Tiananmen.

"I was then assigned to a PLA unit on the outskirts of Beijing," he says. Yan joined the PLA in 1983. A few years later, he went to a military college and graduated in 1987.

When the real Tiananmen loomed in front him, Yan recollects, "I was stunned.

"It's more magnificent and majestic than I imagined. Chairman Mao (Mao's portrait hung on Tiananmen) looked grandfatherly indeed."

He envied children posing in front of Tiananmen for photos. "They were so lucky that they could see Tiananmen at such a young age."

He spent the next day looking at Tiananmen from a guesthouse room in Qianmen, at the southern end of the square. He wanted to see it in the morning, in the afternoon and at night. Yan did not leave his room and had only one piece of bread for the whole day. "I didn't feel hungry. I just felt I couldn't get enough of Tiananmen."

On the third day of his assignment in Beijing, Yan visited the mausoleum of Mao. "Although Chairman Mao did not go to school for long, he was nonetheless a great military master, a great thinker and a great poet," Yan says.

"Mao's success was a combination of talent, hard work and self-discipline."

Yan was assigned to the PLA Logistics Command Academy in Beijing to work as a junior officer after he graduated from the PLA Art Academy in 1993, where he majored in cultural work management. He read extensively about Beijing and Tiananmen, only to find that the existing works were not enough, so he decided to write about Tiananmen himself.

"Tiananmen is a place that embraces great leaders and ordinary people as well," Yan says.

"For me, Tiananmen is a sacred place, that's why I'm so devoted to collecting things related to it. I want to spread what I know to others who are also interested."

Show a photo of Tiananmen to Yan and he can instantly tell in which period the picture was taken. For example, before August 18, 1966, Chairman Mao's portrait was not hung on Tiananmen gate every day, except during the Labor Day holiday in May and the National Day holiday in October, Yan says.

But after August 18, 1966, when Mao received a million "Red Guards" in Tiananmen Square, his portrait was hung on the gate every day.

One of Yan's most treasured items is a photo showing Mao sitting on the ground in front of Tiananmen with Premier Zhou Enlai. It was the night of October 1, 1966, when fireworks were set off in Tiananmen Square to celebrate China's National Day. Mao unexpectedly went out to the front of Tiananmen and sat down to watch the fireworks with the people. Zhou followed and sat with him. Yan says, "The photo shows how our great leaders warmly approached ordinary people in those fanatic times."

The photo was taken by Qian Sijie, Mao's official photographer from 1964 to 1969.

Yan contacted Qian and told him he intended to collect Qian's photos of Tiananmen. "I told him I would pay him for authorization to use his photos."

To his amazement, Qian refused money, but granted Yan the right to use his photos.

Such stories have repeated themselves. Yan's sincerity touched many veteran photographers and they donated their precious images of Tiananmen to his collection.

Meanwhile, many others want to buy his collection, but he has turned them all down. Recently, an American collector offered Yan US$50,000 for a photo album of Tiananmen in the Qing Dynasty (1644-1911). Yan politely declined. "Once a Tiananmen item comes into my hands, it is going nowhere. I did not start collecting to make money and I will never use them to fetch money."

Yan spends hours going through films and slides of old newspapers in libraries, looking for more collectable photos.

A new finding can make him ecstatic. Many histories say Mao first mounted the Tiananmen gate on October 1, 1949, to declare the founding of New China. But Yan found from People's Daily that Mao first ascended it on July 7, when Mao waved his arm and hailed, "Long live the people" to celebrate the 12th anniversary of the victory of the Marco Polo Bridge Incident. Also known as the Lugouqiao Incident, it marked the beginning of China's War of Resistance against Japanese Aggression.

"It's like the joy experienced by two lovers who finally see each other after a period of separation," he says of his finding.

Precious find

One of the most difficult items for Yan to obtain was an envelope picturing a child standing on a rock and holding a telescope to see Tiananmen. It was printed during the "cultural revolution" (1966-76). He got it from a collector in Shenyang, Liaoning Province. When Yan first learned from friends about the envelope, he took a train direct to Shenyang to find the collector and offered to buy it. But the collector said "No."

Yan returned to Beijing, obsessing about that envelope every day. "It is like an addiction, once I see it, I have to have it," he says. "And the little kid on the envelope symbolizes me, cherishing Tiananmen from afar from at very young age."

Yan went back to Shenyang a month later and gave a matchbox printed with a picture of Tiananmen to the collector.

"The matchbox was precious to me too. I realized that I must give him something valuable to persuade him to sell the envelope to me." His sincerity again worked. The collector gave him the envelope as a gift and they became good friends.

Yan's latest project is a compilation of photos taken since 1949, showing ordinary Chinese in front of Tiananmen over the 12 months of every year.

"It's easy to find pictures of national leaders in Tiananmen, but it's not so easy to find photos of ordinary people. So that this project means a lot because it shows that Tiananmen belongs to every Chinese," Yan says.