Colorado was under Spanish control from the 1500s until 1803. Then the United States bought part of it in the Louisiana Purchase. In 1848 the United States won the Mexican War, and got control of all of Colorado.
A long stretch of the Continental Divide is also located in Colorado. The Continental Divide is the North American watershed, the point that determines in what direction water flows. On one side of the mountains, all the water in all the rivers flows to the east, toward the Atlantic Ocean. On the other side of the range, it all goes west toward the Pacific.
Colorado has the highest average elevation of any state, and is full of mountains. People ski here a lot. There are also old ghost towns, old gold-mining towns, and dude ranches (where guests kind of play cowboy by riding horses, hiking, and having campfires).
Mesa Verde National Park is an ancient Native American town, with houses cut right into the cliffs! The cubbyhole-type houses are colored like the cliffs and high up, almost hidden. Climb into one and imagine what it is like to live as high as an eagle — and to worry about where your next drink of water is coming from.
Colorado is the twenty-sixth largest state in population and has a little more than 4 million people. No one city is much larger than the others, but the capital, Denver, has about 500,000 people, and is the largest.