Yam (Mongolian: Өртөө, Örtöö, checkpoint) is a supply point route messenger system employed and extensively used and expanded by Genghis Khan and used by subsequent Great Khans and Khans.

Relay stations were used to give food, shelter and spare horses for Mongol armies messengers. Genghis Khan gave special attention to Yam because Mongol armies traveled very fast, so their messengers had to be even faster, covering 200–300 km per day. The system was used to speed up the process of information and intelligence.

The Yam operated with a chain of relay stations at certain distances to each other, usually around 140 miles or 200 kilometers. Messengers for example would go to the next relay station and give the information to the second messenger and rest and let the second messenger go to the third relay station to hand the document to the third messenger. This way information or documents were constantly on the move without each messenger getting tired. In each relay station there would be spare horses, food, and shelter.

Yam or YAM may refer to:

Route may refer to: