The Earth Day events held on April 22, 1970, drew an estimated 20 million Americans across the country. The two largest gatherings occurred in Washington, D.C., where 10,000 people assembled at the Washington Monument, and in New York City, where a portion of Fifth Avenue was closed to traffic in observance of the event.

This event on May 25, 1986, sought to raise funds for local charities that fought homelessness and poverty, and the idea behind it was ambitious: an unbroken chain of Americans, hand in hand, across the entire contiguous United States. Hands Across America attracted between 5 million and 7 million people—not quite enough to achieve its physical goal, but enough to raise approximately $15 million.

These demonstrations were held nationwide on January 21, 2017, to support gender equality, civil rights, and other issues following the inauguration of U.S. Pres. Donald Trump. According to some estimates, as many as 4.6 million people attended the various events in the United States, making it the fifth largest single-day gathering in U.S. history.