Belgian Princess Mathilde and Crown Prince Philippe ride bikes in Brussels. (Reuters)

Brussels, Sept. 22 (Reuters): Many Europeans woke up today to unusually quiet streets as the annual car-free day kicked off in 1,400 cities around the continent.

From Helsinki to Athens, from Dublin to Paris, citizens from over 30 countries were asked to leave cars at home in a drive to raise awareness of the damage to the environment caused by rising traffic and encourage alternative means of transport.

For many it was a day spent calmly rediscovering the often congested city centres with the family. Public transport was operating as usual, but many took the opportunity to cycle, rollerblade or jog through the ghostly quiet streets.

“We wanted to discover Brussels without the car,” said art-historian Diane Delvaux, who took her seven-year-old John and 21-month-old Othelie cycling through the Belgian capital.

“We like cycling but with the kids it is difficult and we are often obliged to use the car. Today is different. There are hundreds of kids around.”

Brussels, home of the European Commission that launched the initiative in 2000, displayed the strongest commitment to the event by cordoning off 160 square km to traffic, more than any other participating city.

Those who ventured into the city centre before noon were met with the unusual sight of Belgian Crown Prince Philippe and his wife Mathilde on a bike as they approached the Royal Palace after a five-kilometre bike ride from their residence in Laeken. In Paris, where eight districts out of 20 were closed to non-essential traffic, the town hall laid on bicycles and extra boat services on the river Seine.

“It’s lovely. You hear the odd car go by, but on the whole it’s been really quiet. It’s phenomenal,” said central Paris resident Stephen McIlvenna who was enjoying being able to open his windows wide without being deafened by traffic.

Participation was lower in traditionally environment-friendly Germany as the initiative clashed with general elections there. But some cities dared to buck the trend: in Muelheim an der Ruhe, a town of 175,000, the council launched a “walk to vote” campaign. In London, many streets in the centre of the city were blocked by police for a rally by about a quarter of a million country folk in support of fox hunting and against the erosion of rural life.

London Mayor Ken Livingstone urged residents to keep their cars at home and encouraged them to walk across Tower Bridge, which was closed to cars for most of the day.