It's now 8:00 a.m. in Stockholm.

Most people are riding their bikes to work.

Others are going on foot or taking buses.

All the traffic lights are LEDs, and everything is modern and eco-friendly.

Of all the cities in Europe, Stockholm was the one that was named the greenest in 2010.

People there have gone green in many ways.

Green houses collect rainwater for their gardens,

and their electricity comes from garbage.

Over three-quarters of Stockholm's cars and buses run on biogas.

The kind of gas is made from waste water,

and drivers that use biogas can park their cars first in the city.

If going green is the right thing to do for our planet,

then Stockholm is surely a good working example.

Stockholm hopes to use only green energy by 2020.

What's more, all of its cars and trains will run below ground.

That will leave more space for people and nature above ground.

That way, they will not be far away from each other anymore.

Maybe all the other cities in the world should follow Stockholm's example

and make a habit of going green, too.