Global advocacy group Avaaz has coordinated a striking new display, protesting the gun violence that continues to plague the country. 7,000 pairs of children's shoes have been lined up on the southeast lawn of the U.S. Capitol building in Washington D.C., representing every child that's been killed by gunfire since 2012's heartbreaking Sandy Hook elementary school shooting.

In the wake of the shooting in Parkland, Florida, Avaaz has been challenging Congress harder than ever to reform gun legislation. "We are bringing Congress face to face with the heartbreak of gun violence," Oscar Soria of Avaaz told ABC News. "All of these shoes cover more than 10,000 square feet. " Most of the shoes were collected over a two week period, although some were donated by families affected by gun violence, and others were donated by celebrities. "About five families came that were victims of gun violence," Soria said. "It was an emotional moment today."

Tom Mauser was in attendance at the display today, traveling to D.C. in the shoes his son wore when he was killed during the Columbine shooting. "I think this kind of event with shoes offers a very powerful metaphor both for how we miss the victims who once filled those shoes and also for how we see ourselves wanting to walk in their place, seeking change, so that others don’t have to walk this painful journey," Mauser told Avaaz.

Following the display, all the pairs of shoes will be donated to charity.