Ni Dan, 20, and two of his classmates were sitting at the front of a long queue outside Gate No. 6 of the Shanghai Expo Park. They had been there for six hours and it was just 4 a.m. Sunday.

"We chose to visit Expo today for three reasons: it's Expo's 100th day, it's the two-year anniversary of the Beijing Olympic Games, plus it's the eighth day of the eighth month," Ni said. Eight is considered by many Chinese an auspicious number that brings fortune.

Just graduated from a high school in east China's Jiangsu Province, Ni and his friends will have to separate to study in colleges in different parts of China and some will even go abroad. "We want to mark our friendship with this special day," one of Ni's friends said.

Ni and his friends planned to stay in the park for 12 hours after they get in. "We may get tired. But it will be worth it."

The moon was still on the sky when more people were joining the long lines of thousands of people each, five hours before the gate would open.

Sitting on the ground or on 10-yuan (about 1.5 U.S. dollars) plastic foldable stools newly purchased from vendors, people chatted, played cards or meditated to reserve energy for a very long day of waiting, walking, viewing and waiting again.

"It would be a magnificent sight when the gate opens. Just imagine tens of thousands of people all wanting to get in at the same time," said He Wenping, 46, from central China's Hubei Province. On Saturday, she and her daughter came to the gate at 5 a.m. and managed to visit six pavilions. "We plan to finish all of them in three days."