Hundreds of landmarks around the world will shut off their lights this Saturday in observance of Earth Hour 2015.

Earth Hour is an annual event that promotes conservation and sustainable energy. This year organizers say more than 170 countries will participate. London's Big Ben, New York City's Times Square, Paris' Eiffel Tower, the Acropolis in Athens and even the International Space Station will go dark for a full 60 minutes.

(MORE: )

The World Wildlife Fund began Earth Hour in 2007 in an effort to raise , according to the organization's website.

The event will take place at 8:30 p.m. in each location's respective time zone.

MORE ON WEATHER.COM: Earth Hour around the World

Earth Hour being celebrated in Pontianak, 2013. (WWFIndonesia/earthhour.org)