, seen in the background, at left. Though many riders bring their own bicycles, the participants maintain a "Zoobomb pile". This is a tower of minibikes anchored to a bicycle rack at the Zoobomb meeting point. These are spare bikes that are used as loaners for would-be Zoobombers who don't have their own bike. The pile has become a local landmark. In March 2009, a new pile was dedicated, in a ceremony attended by Portland mayor
Sam Adams. The new pile is located at SW 13th and Burnside. ==Related events==