How did your city celebrate Earth Day?

On this year’s April 22, more than one billion people in 190 countries around the globe will participate in the 42nd Anniversary of Earth Day. With over 800 million environmental actions registered on the Earth Day Network and world-wide held events, the Earth Day 2012 campaign is designed to increase awareness and appreciation of the Earth's natural environment and provide people with the opportunity to unite their voices in a call for a sustainable future.

The Earth Day movement's grassroots history goes back to the 1960s when environmental activism inspired U.S. Senator Gaylord Nelson of Wisconsin to create a day of national celebration. Nelson organized the first Earth Day on April 22, 1970, with the help of Denis Hayes, an activist and graduate student at Harvard University, who took it international in 1990. In only 40 years, Earth Day has evolved from a single day celebrating the environmental movement in the United States to a global network. Despite the pact, and the visible environmental damages that prompted such actions, environmental threats still loom large.

Cities are on the front lines when it comes to adapting to climate change. But as vibrant cultural centers with multitudes of professionals, artists, and academics, cities can mobilize residents in effective and creative ways. This Earth Day, cities stepped up once again to rally their citizens and participate in what has become an important day of global awareness-building and action.

Here are a few highlights of how C40 Cities around the world celebrated. Read to the bottom to see how to share your city’s story:

  • Caracas, Venezuela participated in the One Day on Earth screening. VITALIS, a Venezuelan NGO, is also hosting “Twittertón por La Tierra,” which was a marathon of tweets about Earth with facts, tips and descriptions of Earth Day. “The Lorax” was also screened to promote environmental protection.
  • Dhaka, Bangladesh participated in One Day on Earth screening as well as “Let’s Do It World: Bangladesh,” part of the World Cleanup 2012 Initiative that strives to clean up illegal waste across the country.
  • Lima, Peru had 50,000 trees planted in the city by Vidas Verdes, a local ecological association.
  • Melbourne, Australia hosted the largest Earth Day picnic in Australia at the Melbourne market.
  • Mumbai, India had numerous organizationally-driven events, including an E-Waste Collection Drive by Atterobay Recycling, a leading electronic waste recycling company, a children’s ride hosted by Mumbai Cycling Enthusiasts, and Fotothon 2012 – a 24-hour competition for environmentally-related photos.
  • Toronto, Canada had a multitude of offerings for Earth Day, with events ranging from clothing drives to educational activities to community recycling and clean-up efforts. The celebrations are continuing into this week, culminating with an Earth Day Canada benefit concert and film screening.
  • Warsaw, Poland’s Warsaw Community Coalition and the Warsaw High School Environmental Club planned an Earth Day Festival which includes a city clean-up, e-waste recycling centers and environment-related exhibits.

But we would like to hear from you as well. Did your city celebrate Earth Day? If so, tell us how! Let us know on Facebook or Tweet at us with the #ycities hashtag.