A 4,000 foot high cave burial in Mongolia contained an almost perfectly preserved wooden saddle. The burial also had a compound bow, arrowheads, a leather quiver with an iron hook, and a wooden vessel. Archaeologists believe, based on carbon dating, that the burial dates to the middle of the fourth to fifth century, or perhaps the beginning of the sixth century. They believe that the person buried in the tomb who was accompanied by a horse was a Rouran warrior.
For more information, please see the published article at the Bulletin of Archaeology, Anthropology and Ethnography here.