DISCOVERING THE KIGER MUSTANG: The Kiger Mustang was discovered in the Kiger Mountains of eastern Oregon in 1977 but the genetic heritage goes back to the Spanish horses and the ancient Sorraia of Iberia. These horses are very smart and rare, they are dun in color with black manes and black tails. They were brought over by Columbus. They were discovered on my ancestors' land and that is why they are called the "Kiger" Mustang.