Fernando Traverso's Bicis

On March 24, 2001, Fernando Traverso, an Argentinian hospital worker, political activist, and artist, began spray painting a series of twenty-nine life-sized bicycle stencils throughout the streets of his home town Rosario as a symbolic memorial to his twenty-nine friends who were abducted, tortured and killed during Argentina's Dirty War. Today, there are 350 bici stenciled images painted on buildings throughout Rosario, memorializing each of its 350 citizens who were disappeared under Argentina's military dictatorship and National Reorganization Process (1976–1983).

Source: Wikipedia — Fernando Traverso's Bicis (CC BY-SA 4.0)