Tian'anmen Gate Tower, to the north of Tian'anmen Square

If you are planning to spend Saturday under the autumn sun in Tian'anmen Square, forget it.

The square, in the heart of Beijing, will be beyond public access until early Sunday morning. The first rehearsal for the grand parade to celebrate the 60th anniversary of the establishment of the People's Republic of China will be held from 3 am on Saturday to 2 am on Sunday.

The rehearsal, involving about 200,000 people and 60 floats, will be divided into three parts, according to the 60th National Day Celebration Preparation Committee of the Beijing municipal government.

The mass pageant parade rehearsal will be held from 3 am to 5 am on Saturday, followed by a background performance on the square from 8:30 am to 10 am. The dancing and singing gala will be a three-hour affair, from 11 pm on Saturday to 2 am on Sunday.

To ensure that the rehearsal is held smoothly and to maintain the secrecy until the National Day (Oct 1), Tian'anmen Square and its adjacent roads will be off limits to the public, except participants and officials, from 8 pm on Friday, the city's traffic bureau said.

Service on subway lines 1 and 2 will be disrupted between 10 am and 1 pm on Saturday because trains will carry only participants. No trains or buses will stop at Tian'anmen.

Visitors to the Forbidden City will have to enter and exit from the north gate on Saturday because the one facing Tian'anmen Square will be closed.

The Beijing Working People's Culture Palace, the National Museum and Chairman Mao Memorial Hall will be also closed.

Security has been tightened in and around the square, more cameras have been installed, and more policemen, in uniform and plainclothes will patrol the area.

But the rehearsal is not only about inconvenience. It has many pleasant surprises, too.

A sophomore from the University of International Business and Economics surnamed Du said he forced himself to sleep for four hours on Friday afternoon because he has a sleepless night ahead.

Du said that along with thousands of college students, he had to reach Tian'anmen Square at 9:30 pm and stay there until early Saturday morning for the rehearsal.

But Du is not complaining. "I've been undergoing training for the parade since July 26," he said excitedly. "Finally, it is time see how it has worked out."

Guo Jue, a sanitation worker who installs temporary toilets near Tian'anmen, is having a busy time, too. She has to work for 41 hours at a stretch from Friday noon, she said, to prevent those taking part in the rehearsal from using the toilets that are not ready.

The city authorities are installing 211 temporary toilets on both sides of Chang'an Avenue near the square.

Working long hours at night has always been boring and exhausting, but Guo is excited because she can watch the rehearsal and might be able to see her daughter in the parade, too.

Wang Rui, a Tianjin resident who has booked into Beijing Hotel in Chang'an Avenue with his daughter, was surprised to learn about the restrictions on traffic and people's movement on Saturday. He said he had to cancel his planned visit to the Bird's Nest on Friday night.

But since he has booked into a room with windows facing the Chang'an Avenue he can see part of the rehearsal, he said.

"That is what I call a surplus surprise," Wang said.

But Wu Liantong, a taxi driver, felt troubled. He said it would be difficult to convince passengers on Saturday that they cannot go Tian'anmen Square.