Thousands of people visited the small northeast Missouri town to celebrate the holiday this weekend.
One of the favorite attractions is the town's small post office, which celebrated its 100th anniversary of delivering letters.
Every week, only a few people drive by or even walk inside, but on one weekend in the month of March, hundreds of people walk through its doors to get the special cancellation coat.
It’s the only place in the world that shares the same name as the Irish holiday.
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