Crazy kids stretch huge waterslide down steep city street, urban surfing is born (VIDEO)

YouTube screen capture

SAN FRANCISCO, Calif -- Summer means slip-n-slides for kids across the U.S.

But in San Francisco kids of all ages decided the lawn just wasn't enough for their slide and took to one of the city's famous hills.

Devin Graham dubbed it 'urban surfing' in the video he made of the adventure.

In the short film dozes of people can be seen sliding, surfing, belly-flopping down a giant waterslide stretching down a city street and ending in a huge inflatable pool.