COLOMBIA-CAR FREE DAY

That bike-friendly city of Bogota finally came to the conclusion that two wheels are worth seven days, not just one. The Colombian capital, which has been hosting car-free days regularly since 2000, expanded the idea and held its first-ever car-free week earlier this month, Treehugger says. Coordinated by the organization "Mejor en Bici" ("Better on Bike"), the event spurred about 600,000 people a day to leave their cars at home.

The city of about seven million people has always been ahead of the game when breaking out its inner Pee Wee Herman. During the 1970s, Bogota hosted its first Ciclovia, in which major city routes were shut down for car use on Sundays and holidays so that bikers could have free reign. Ciclovias have since popped up all over the world (Los Angeles, for one hosts its CicLAvia twice a year).

Bogota city leaders, where car crashes accounted for 570 fatalities last year, are pushing for expanded bicycle use as a way to cut both traffic and air pollution. Bogota made news last September on the green-car front when 45 BYD e6 electric vehicles were put into use in the city's taxicab inventory. That gave the city the largest all-electric taxi fleet in South America.