Landmarks around the world go dark for Earth Hour - WBRC FOX6 News - Birmingham, AL

(RNN) - Cities around the world turned the lights off at major landmarks in observance of Earth Hour 2013.

At 8:30 p.m. local time Saturday, power users were asked to turn off the lights for one hour to raise awareness of environmental issues.

Across the globe, the lights were turned out at sites like the Sydney Harbor Bridge, London's Big Ben and Parliament buildings, and at Moscow's Kremlin and St. Basil's Cathedral.

In the United States, companies, landmark buildings, communities, and other groups pledged to take part. Major landmarks that went dark included Willis Tower (formerly Sears Tower), the largest building in North America, the Empire State Building and Rockefeller Center in New York and the Las Vegas Strip.

San Francisco was selected as the U.S. Earth Hour City Capital, picked from a group of 29 cities participating in the World Wildlife Fund's Earth Hour City Challenge, stated the World Wildlife Fund in a press release.

The city challenge initiative recognizes those locales preparing for increasingly extreme weather and promoting renewable energy.

San Francisco, along with Earth Hour City Challengers Chicago and Cleveland, will receive the WWF's Earth Hour Climate Leaders Award and $30,000 to support local climate action efforts in their communities.

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