Green Chicago River St Patrick's Day Postcard

Each St. Patrick's Day the Chicago River is dyed green. The tradition started by accident when plumbers used green dye to trace sources of illegal pollution dumping.

Size: 4"x6"
Paper: 110lb cardstock with a smooth matte finish
Back: Includes fascinating facts about the postcard scene

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CHGO-199 | © Christopher Arndt Images. This derivative work is based on an original photograph by Natasha Jelezkina and used under Creative Commons license (CC BY-SA 2.0).