DENVER, Colo. (CBS4) –  Happy 140th birthday, Colorado!

That’s right, on this day in 1876, our beautiful state was the 38th to join the Union, which is why, today, we’re celebrating Colorado Day.

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Now, before we go on, do you know what’s significant about the year 1876? It’s 100 years after the United States declared their independence. That’s why one of Colorado’s nicknames is the Centennial State.

Our history goes back long before that, though. Long before the gold rush. Long before Lieutenant Zebulon Pike mapped the boundary of the Louisiana Purchase, which included the eastern half of present-day Colorado. And we go back long before the Plains Indians roamed the land and the Ancestral Puebloans lived in the Four Corners region.

So what’s before all that?

We’re talking the dinosaurs, evidence of which can still be seen in the Denver metro area. We’re talking the Rockies. And we’re talking the red rock that gave our state its name.

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Spanish explorers referred to the area as “Colorado” because of the red-colored earth, most specifically the silt found in the Rio Colorado.

Initially, the river wasn’t named that at all. It was called the Grand River. It wasn’t until an act of Congress (seriously) in 1921 that it was changed to the Colorado River.

All of this beauty is why tourism is one of the biggest parts of our economy. The skiing, the hiking, the rafting, and everything else; it’s why people want to visit Colorado. And it’s why so many of us, more and more each day, decide to call Colorado home.

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