Group of young Carthusian horses coming in from pasture, Yeguade de la Caruja, Jerez, Spain

The Carthusian is one of Spain's oldest and purest breeds, with one of the oldest stud books in the world. One particular characteristic of the Carthusian is the warts found under its tail, and bony growths on the forehead, resembling horns. Both are from the foundation stallion, Esclavo.