Quadripoint
The Four Corners Monument is the only point in the United States where four states meet: Colorado, Utah, New Mexico, and Arizona meet at right angles. The United States first acquired the area now called Four Corners from Mexico after the Mexican–American War in 1848. In 1863 Congress created Arizona Territory from the western part of New Mexico Territory. The boundary was defined as a line running due south from the southwest corner of Colorado Territory, which had been created in 1861. By defining one boundary as starting at the corner of another Congress ensured the eventual creation of four states meeting at a point, regardless of the inevitable errors of boundary surveying. The monument is centered at .
Fifth Circuit Four
The "Fifth Circuit Four" (or simply "The Four") were four judges of the United States Court of Appeals for the Fifth Circuit who, during the late 1950s, became known for a series of decisions (which continued into the late 1960s) crucial in advancing the civil and political rights of African Americans; in this they were opposed by fellow Fifth Circuit judge Ben Cameron, a strong advocate of states' rights. At that time, the Fifth Circuit included not only Louisiana, Mississippi, and Texas (the limits of its jurisdiction since October 1, 1981), but also Alabama, Georgia, Florida, and the Panama Canal Zone.