"By this action we want the city dwellers to realize it is possible to get around by public transportation or walking," said Aado Kuuse, chief specialist of the Tallinn transportation department.
Kuuse added that there was no point of using a car every time and everywhere. "Other vehicles exist and, anyway, walking is conducive to (good) health," he said.
The program of the car-free day also includes a bike parade on one of the bike lanes built this year near the Hippodrome to Rocca-al-Mare, and promoting roller-skating as an alternative mode of transport.
More buses will be in service on car-free day, and one of the tram lines will run additional trams.
Traffic police will also work more intensively and direct cars that emit a lot of smoke and heavy trucks out of the city center.
In the Baltics, Vilnius will also unofficially support a car-free day.
The car-free day has become a traditional event in many European cities, especially in Italy and France.
The first car-free day held in 35 French cities in 1998 set an example, and now about 200 European cities annually participate in the event.
In Europe, over 50 percent of emissions of polluting agents such as nitrogen and carbon oxides come from road transport vehicles.
Nevertheless, a summary of the project, published on the environmental depart-ment's Web site (http://tallinn.tallinn.ee/keskkonnaamet), says Tallinn is not yet ready to join the car-free day movement formally. To do so, a city must undertake a number of actions, such as making some districts 100 percent car-free.
"By leaving your car at home this day, you appreciably improve traffic and the environmental situation for the benefit of bikers and pedestrians," says the Web site.
Officials hope tens of thousands of Tallinners will observe the event. "We think about 10 percent of Tallinn residents will follow the appeal of the city government and go to work by alternative transport. Hence, there should not be any problems with parking," said Kuuse.
"Certainly, not all drivers will leave their cars at home, and that is not what we are hoping for. Tallinn's public transportation system would not be able to cope if all drivers decided one fine day to take a bus," deputy mayor, Priit Vilba told BNS.
Tarmo Pauklin, head of the air protection department of the Tallinn environmental department, said the idea of carrying out the car-free day in Tallinn was the environmental depart-ment's. "Last year the city government discussed the project, but nothing came out. This summer the event was reconsidered," he said.
Similar days in other parts of Europe show car-free days make cities cleaner and reduce the noise level by up to 50 percent. The same effect is expected in Tallinn.
Pauklin said the quality of air in Tallinn is relatively good. In spite of the rapid increase in the number of cars, the air concentration of main polluting agents - nitrogen oxide and carbon monoxide - has been steadily decreasing. According to the Tallinn transportation department, there are 386 cars for every 1000 residents of the city.
In contrast with other social projects held in Tallinn, the car-free day is not widely promoted. No posters are up around the city, and only a few articles have appeared in the newspapers.