June 21, 2008 (May 18, 2008 in the lunar calendar) was the first "Asian Lights Out Day". Earth Hour Asian Lights Out Day is an environmental event that lights out on the summer solstice in the northern hemisphere (the day with the longest sunshine in the year). The event began in 2008 and aims to advocate cities in Asia to turn off lights for one hour (9: 00 - 10:00 p.m.), in order to draw people's attention to increasingly serious environmental issues, and at the same time advocate people to choose energy conservation and emission reduction, care for the environment, A lifestyle that opens their hearts and is friendly to interpersonal relationships. Since 2008, dozens of cities in Asian countries such as Japan, Singapore, South Korea, and China have decided to designate this day as "Asian Lights Out Day" and hold lights-out activities on this day at the same time. At 8:30 pm on June 21, 2008, more than 20 Asian cities echoed the event. Skyscrapers on both sides of Hong Kong's Victoria Port will turn off lights for an hour along with many buildings in Taipei, Beijing, Guangzhou, Tianjin, Tokyo, Seoul and other cities.