Image pulled from Huffington Post article listed below
The first time the red shoes made their debut was in 2009 in Ciudad Juárez with 33 pairs of shoes. Each pair of shoes donated to the performance represents a woman who died, or disappeared, and bears witness to the violence perpetrated against women.
The creator of this initiative is the Mexican artist Elina Chauvet who has, through a network of associations from around the world, taken Zapatos Rojos on tour. The work tells the story of violence and blood in Ciudad Juárez, a city on the northern border between Mexico and Texas. Since then, Zapatos Rojos has travelled the world from Mexico to Italy and beyond, adding to a testimony of suffering and death. In 2012, people going to work in the city centre of Milan who passed from the columns of San Lorenzo found these red shoes.
You can read more about this resource here.