Motorcycles are the mode of choice to get around in Medellín, Colombia. In the working-class districts that climb the steep slopes of the Valle de Aburrá, residents have self-built elaborate neighborhoods outside of formal urban planning. While humans can walk up steps, wheeled vehicles require ramps. From the basic need to wheel your bike inside at night, a vast assortment of small ramps has emerged. These ramps possess a sculptural and expressive quality, and constitute a kind of folk br...