The state was named for the Colorado River, which Spanish travelers named the Río Colorado for the ruddy (Spanish: colorado) silt the river carried from the mountains. The Territory of Colorado was organized on February 28, 1861, and on August 1, 1876, U.S. President Ulysses S. Grant signed Proclamation 230 admitting Colorado to the Union as the 38th state. Colorado is nicknamed the "Centennial State" because it became a state a century after the signing of the United States Declaration of Independence.
Kentucky is known as the "Bluegrass State", a nickname based on the bluegrass found in many of its pastures due to the fertile soil. One of the major regions in Kentucky is the Bluegrass Region in central Kentucky, which houses two of its major cities, Louisville and Lexington. It is a land with diverse environments and abundant resources, including the world's longest cave system, Mammoth Cave National Park, the greatest length of navigable waterways and streams in the contiguous United States, and the two largest human-made lakes east of the Mississippi River.