William Ferguson wrote the following in the April 20, 2008 New York Times T Magazine:
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Ghost Bikes

To judge from ad campaigns and civic initiatives, the solution to climate change is simple: ride a bike, save the earth.

The hundreds of ghost bikes throughout the world, however, silently testify to a darker truth. A memorial to a cyclist killed in traffic, a ghost bike springs up in the days after the crash — never, in the parlance of the cycling activists responsible for the ghost bikes, an “accident.”

It is spray-painted stark white and chained to a street sign and often bears a commemorative plaque. Unlike the crosses on highway shoulders, briefly noted in a passing blur, ghost-bike memorials are sidewalk monuments meant to spark debate, if not dread.

These eerie urban shrines stand as reminders that however free and healthy and green our bicycles make us, the green revolution might actually be a revolution, and revolution can be dangerous.
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Fred Conrad photographed six of them (above and below)

for the New York Times.