Seoul's landmark buildings will pull the plug Saturday evening to observe Earth Hour, an annual event raising environmental awareness around the globe.

The Seoul Metropolitan Government said lights at Seoul's N Seoul Tower on Mount Namsan, the skyscraper 63 Building and the country's number one national treasure, Sungnyemun Gate, will be turned off for an hour from 8:30 p.m. on Saturday. 

All Seoul city government buildings and public facilities will also participate in the movement, including all bridges across the Han River and the statues of King Sejong and Admiral Yi Sun-shin in Gwanghwamun Plaza.

The Seoul government will encourage major department stores, shopping outlets and hotels that have more than ten floors as well as stores and houses to voluntarily take part in the lights out event.

Around 180 countries around the world are set to turn off their lights for an hour beginning at 8:30 p.m., as part of the movement which was initiated in 2007 by the World Wide Fund for Nature.