Traffic flowed more smoothly but the sun was still shrouded by smog on Monday, the fourth and final day of Beijing's Olympic pollution prevention test.
To see if the city's poor air quality could be improved at least temporarily during next August's Games, the Chinese capital has taken up to 1.3 million cars off the roads by banning number plates ending in odd and even numbers on alternate days.
State media proclaimed the exercise a success, with the Xinhua news agency claiming late on Monday that the city had four "blue-sky days". But the skies -- and some athletes -- suggested a mixed verdict.
Seoul used similar traffic control measures when it hosted the Olympics in 1988, and Athens battled its pollution problem with the same tactics for more than a decade before it held the Games in 2004.
Pollution remains the main concern for organisers of the Beijing Games. Olympics chief Jacques Rogge said two weeks ago that some endurance events might have to be postponed if air quality was not up to scratch.
One such event is the 174-km (108-mile) cycling road race, and some of the world's top cyclists were in Beijing over the weekend for a test event.
Despite taking more than a third of Beijing's cars off the roads and a race course that took in the less polluted climes around the Great Wall, there were clearly respiratory issues for some competitors.
"I have a sore throat and lungs but unless we get everyone to stop driving for a month I guess there is not a lot we can do about it," Tour de France runner-up Cadel Evans told Australia's Sunday Telegraph after the road race.
