What the world's most advanced traffic system can—and can't—do for the city that invented gridlock.

What infrastructure mystery keeps you up at night? Submit your Service Request by recording a voice memo with your question and emailing it to servicerequest@99pi.org.

Service Request is a production of 99% Invisible and Campside Media.

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The surprising power of a simple phone number to connect a community.

What infrastructure mystery keeps you up at night? Submit your Service Request by recording a voice memo with your question and emailing it to servicerequest@99pi.org.

Service Request is a production of 99% Invisible and Campside Media.

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How one wealthy, amateur astronomer convinced the world Martians were real.

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For centuries, the world's greatest minds were stumped by the deadly mystery of longitude, until an obsessive underdog entered the fray and changed navigation forever.

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This is the seventh episode of our ongoing series breaking down the U.S. Constitution.

This month, Roman and Elizabeth discuss Article IV, which outlines the relationship between states and between states and the federal government. They add the 10th Amendment to the conversation, because that also talks about the states.

Then, California Attorney General Rob Bonta joins to talk about how his office is using Article IV and the 10th Amendment to protect the state from federal overreach.

The 99% Invisible Breakdown of the Constitution

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How a fence meant to protect sheep transformed the entire Australian landscape.

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How a small Mexican border town transformed itself into the dental tourism capital of the world, where dental care costs up to 80% less than what it might cost in the United States.

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Idaho was the first state to slap a slogan on a license plate, “Idaho Potatoes,” which may not seem like a big deal, but it turns out this idea would end up having outsized consequences, and not just for Idaho. Because what started in one state would soon spread. And when it did, the question of what should go on a license plate, and what shouldn't, would prove surprisingly contentious.

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