Paris on Monday resorted to drastic measures to curb soaring pollution levels by forcing all cars with number plates ending in even numbers off the road for the first time in two decades.
Around 700 police officers were deployed to man 60 checkpoints around the French capital to ensure that only cars with number plates ending in odd numbers were out on the streets.
Public transport has been free since the weekend to persuade Parisians to leave their cars at home, and the state railway company SNCF warned on its website of packed suburban trains at peak hours due to the extreme measure.
“It is sure we will have more clients today,” a delighted taxi driver told AFP.
“There are people who take their car because they don’t want to be pressed up against others in the metro. Today they will take a taxi.”
The restrictions came into force across Paris and 22 surrounding areas from 5:30 am (0430 GMT).
They will be reviewed on a daily basis, with odd numbers potentially banned on Tuesday if an extension is deemed necessary.
Parking will be free for vehicles with even number plates, the Paris city hall said, calling on residents to consult carpooling or car-sharing sites to work out their travel plans.
However not everyone seemed to be aware of the ban, or chose to ignore it.
“You don’t have the right to drive with your number plate,” a man on a scooter remarked to another while stopped at a red light.
“Oh really? I didn’t know,” the second driver replied before speeding off.
Those who choose to brave the ban risk a fine of 22 euros ($30) if paid immediately, or 35 euros if paid within three days.