The Great Depression, the civil rights movement, the Vietnam War, abortion, black rights, gay rights, immigration. For generations a host of issues have drawn massive protests to Washington as people seek to be heard by the federal government.
Saturday's women's march is no different, with hundreds of thousands traveling from around the country to fight for women's rights.
But this latest march, which comes on the heels of President Donald Trump's inauguration, took on a life of its own, with many of those gathered expressing their disapproval of Trump, as well as some of the policies that had marked his colorful campaign.
A look at protests, past and present, as captured by The Associated Press.