When you look at a map of the United States, you start to see that the further West you move, the more rectangular the states become. The "Four Corners" states create 4 individual boxes, that zoom out to a larger, rectangular area.

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Except for the left-side border with California - that's where things start to get a little jagged. And that sharp angle at the bottom of the state. What's up with that?

Sharp Borders, Distinctive Shape

Have you ever wondered how Arizona got its distinctive shape? Two sides of the state are mostly straight borders and sharp corners.

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Greetings from all four corners. Image // via Canva
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So why isn't the western and southern border straight? To find out, you have to delve into the history of how Arizona became a state.

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Arizona Territory

Long before it entered the union, Arizona began as a territory. It was part of the Mexican territory of Alta California, which was ceded to the United States after the Mexican-American War in 1848.

The Treaty of Guadalupe Hidalgo established the border between Mexico and the United States along the Gila River, which runs through Arizona.

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The Four Corners - stand in all four states at once! Image // via Canva
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According to Wikipedia, in 1863 President Abraham Lincoln signed legislation dividing the New Mexico Territory into two approximately equal pieces, creating the Arizona Territory out of the western half.

At that time, the US wanted more land south of the Gila River. They were looking to build a railroad route to California.

The Gadsden Purchase

This led to the Gadsden Purchase which was signed in 1853. Mexico sold about 30,000 square miles of land to the United States for $10 million. The Gadsden Purchase added a strip of land to the southern edge of Arizona, which created the bottom part of the state's shape.

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Happy Valentine's Day. Love, Arizona

Arizona became a state on Valentine's Day, 1912, becoming the 48th state to join the Union. The boundaries of Arizona have not changed since then, except for some minor adjustments with neighboring states.

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Arizona's shape is all part of the historical and geographical origin of our state. And it's also part of the fabric of the history of our role in the expansion of the United States.

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