Earth Day is an annual event celebrated on April 22.
It started in the United States in 1970.
Two decades later, in 1990, Earth Day went global, mobilizing 200 million people in 141 countries and lifting environmental issues onto the world stage.
Earth Day 1990 gave a huge boost to recycling efforts worldwide and helped pave the way for the 1992 United Nations Earth Summit in Rio de Janeiro.
Now Earth Day is celebrated by more than a billion people every year.
Canadian Prime Minister Justin Trudeau issued the following statement for Earth Day:
"Today, we join the global community to celebrate Earth Day – a time to connect with nature and reaffirm our commitment to build a cleaner, more sustainable world for our children.
"As Canadians, we have a responsibility to safeguard our planet and natural treasures. I am proud of the steps our Government has taken to protect the environment and promote clean growth. These steps include historic domestic and international agreements that will help us respond to pressing environmental challenges, grow the economy, and build a cleaner, healthier tomorrow.
"On Earth Day, we recognize Indigenous cultures that have long understood the intricate links that exist between land, water, air, and all living things. Ensuring that decisions today serve generations tomorrow requires an active effort from all of us.
"Canada looks forward to hosting World Environment Day on June 5 this year. Like Earth Day, it will be an occasion to celebrate our connections to our environment and to each other.
"On behalf of the Government of Canada, Sophie and I encourage all Canadians to take a moment today to go outside, find renewal in nature, and appreciate the environment that connects us all."