During Earth Hour on March 27 at 8:30pm, hundreds of millions of people around the world will turn off their lights for one hour as a call to action on climate change.

From Mongolia to Argentina, the Arctic to Antarctica, from the Cook Islands to Russia and across the United States, lights at homes, businesses, government buildings and iconic landmarks will dim, making the switch toward creating a cleaner, safer and more secure future.

Already a record 115 countries have joined the movement and 6,000 cities are projected to participate.

In the U.S., 26 states have officially pledged to observe Earth Hour: Arkansas, California, Colorado, Connecticut, Delaware, Georgia, Illinois, Iowa, Kentucky, Massachusetts, Michigan, Missouri, Montana, Maryland, New Hampshire, New York, Ohio, Oklahoma, Oregon, Pennsylvania, Rhode Island, Tennessee, Vermont, Washington, West Virginia and Wisconsin.

Lights will be dimmed at some of the U.S.’s most iconic landmarks including Mount Rushmore in South Dakota, St. Louis’ Gateway Arch, Sea World in Orlando, the Las Vegas Strip, New York’s Empire State Building and Chrysler Building, the Golden Gate Bridge in San Francisco, Washington D.C.’s National Cathedral, California’s Santa Monica Pier, and the Space Needle in Seattle. Internationally the Brandenburg Gate, Eiffel Tower, Hiroshima Peace Memorial, India Gate, and the world’s tallest building Burj Khalifa in Dubai, UAE are all participating.

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