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.
Arkansas is the 29th largest by area and the 33rd most populous of the 50 United States. The capital and most populous city is Little Rock, located in the central portion of the state, a hub for transportation, business, culture, and government. The northwestern corner of the state, such as the Fayetteville–Springdale–Rogers Metropolitan Area and Fort Smith metropolitan area, is a population, education, and economic center. The largest city in the state's eastern part is Jonesboro. The largest city in the state's southeastern part is Pine Bluff.