People pack the World Expo site yesterday at its first trial operation.?

Under drizzly skies and with only a handful of nations' pavilions open, 200,000 people, mostly Shanghai residents, got the first views of the World Expo 2010 site?on April 20?at the event's first test operation.

There was excitement amongst the crowd, but also some frustration over the incomplete state of the grounds during the preview.

The China Pavilion was the most popular spot.

But some visitors were miffed to learn they had to walk for 10 minutes to the nearest reservation machines, queue to reserve a time to tour the pavilion, and then line up again in front of the iconic building with their reservation tickets in hand.

Big crowds formed at the Expo's main entrance on Yaohua Road in Pudong, but Zhang Guangsui, a 66-year-old local retiree, had a quicker time getting in at the Luban Road entrance on the site's Puxi side, where fewer people queued up.

Luo Jing, 32, said even fewer people were at the Dongchang Road Water Gate, which takes people by boat to the corporate pavilions' region in Puxi site.

Luo said he had an easy time making a reservation for the China Pavilion at one of Puxi's less-heavily used machines.

Wu Lirong, 65, lined up for a long time to have lunch. She suggested visitors bring some bread and to take a late lunch after others finished.

Water and drinks will be prohibited at the entrance, but non-liquid food and fruits are permitted.

Visitors found some things to praise during the test run.

Chen Yuexiang, who took her 91-year-old mother on a wheelchair to the Expo site, said workers at the China Pavilion opened a special channel for them to visit the pavilion and the accessible facilities were perfect.

The security measures at the entrance are careful and make visitors feel safe, said Ken Garrett, a 45-year-old general engineer from Atlanta, the United States.

Lu Yingying, a 73-year-old retired English teacher, said the volunteers were extremely patient and helpful.

The China Pavilion and the five Theme Pavilions opened to visitors yesterday, along with all the 18 corporate pavilions and the Urban Best Practices Area in Puxi.

Foreign pavilions taking part in the soft opening included Australia, New Zealand, Luxembourg, Sweden, United Kingdom, Pakistan, Saudi Arabia, Italy, and, partially, the United States.

The organizer said more pavilions will open to visitors in the following five test operations through April 26.

The medical station run by Shuguang Traditional Chinese Medicine Hospital and Changhai hospital received 37 patients yesterday, none with serious injury.

"People, especially the elderly and children, must take care in crowded place," said Wang Ziying, an official of Shuguang TCM hospital. "Band-aids and painkiller were the most popular," said Dr Sha Li, who served at the medical station.

"Many people just had the skin rubbed off on the fingers and toes," Sha said.

"We suggest visitors wear comfortable shoes and take a rest regularly while walking around the Expo zone. Those with chronic diseases better take medicines with them."