Cars with even-numbered license plates will be banned from the city's streets Friday and Sunday, from 6:00 a.m. until midnight.
Odd-numbered cars must stay off the roads or face a fine Saturday and Monday.
The experiment appears to be a success so far, with significantly fewer cars on city streets, a RIA Novosti correspondent said.
As many as 8.4 million people are expected to take public transport during the four days of the experiment, compared with 6.4 million on average. To cope with the extra burden on public transport, the number of buses was increased and their working hours extended by an extra hour.
Seoul used similar measures to cut traffic when it hosted the 1988 Olympic Games, and Athens managed to stop pollution for a decade before it hosted the Olympics in 2004.
