Zoobombing in Portland, Oregon
The US city of Portland in Oregon is home to a unique weekly cycling event known as zoobombing.
It attracts an eclectic crowd of cycling enthusiasts who like nothing more than hurtling down a steep hill at high speed, on souped up children's bikes, late at night.
Some of the bikes are left chained up in a pile in the city centre, which has itself become a local landmark. The ride, often repeated several times in an evening, starts with a journey on Portland's light rail system then a hike to the top of a hill, near the city's zoo.
Peter Bowes went along to see the zoobombers in action.
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- From the section US & Canada