We believe one artist has painted the pictures, he takes one panel at a time with the owner's permission. When finished he puts them back up. Pretty cool.
Other than the ones designed for input by the public, I believe the fences are private and cannot be painted on without the owner's permission
This a good question, from what I know I believe it is an artists that paints the trail, but at some parts of the trails there are chalk boards were people write messages or make drawings. They even left Crayola chalks for people to use.
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