The horse of the Iron Age was still relatively small, perhaps high (measured at the withers.) This was shorter overall than the average height of modern riding horses, which range from about . However, small horses were used successfully as light cavalry for many centuries. For example, Fell ponies, believed to be descended from Roman cavalry horses, are comfortably able to carry fully grown adults (although with rather limited ground clearance) at an average height of Likewise, the Arabian horse is noted for a short back and dense bone, and the successes of the Muslims against the heavy mounted knights of Europe demonstrated that a horse standing can easily carry a full-grown human adult into battle.