The Arabian or Arab horse is a breed of horse with historic roots on the Arabian Peninsula. With a distinctive head shape and high tail carriage, the Arabian is one of the most easily recognizable horse breeds in the world. It is also one of the oldest modern breeds. Although modern DNA cannot trace breed purity in the modern population beyond 200 years, there is archaeological evidence of horses in the Middle East with landrace characteristics that resemble modern Arabians dating back 3,500 years. Arabian horses have spread around the world by both war and trade, being used to improve other breeds by adding speed, refinement, endurance, and strong bone. Today, Arabian bloodlines are found in almost every modern breed of riding horse.