In 1970, then-U.S. Senator Gaylord Nelson, a Wisconsin Democrat, helped created Earth Day, an occasion meant to bring attention to emerging environmental problems. Since then, the now-worldwide, roll-up-your-sleeves day of activism has become popular in local communities everywhere.

One billion people are expected to participate around the globe, according to CNN. As Wired states, Earth Day is a time to “tell your mother you love her”–Mother Earth, that is. Of course, the action takes place at the local level, as well, and The Denver Post has a list of events around the state. In Fort Collins, numerous events are planned all week, writes the Coloradoan.

And there’s lots to think about. The Colorado Springs Independent, for instance, reports on the Fountain landfill, where residents of El Paso County tossed out more than a million cubic yards of trash in one year–comparable to a 15-story building.