Fascinating article from USS Clueless about the Mongols. I'm particularly interested because the Mongols are the only miniatures army I have ever had the persistence to paint (in adult life anyway).
In the mechanized age of blitzkrieg in the 1940's in Europe, an advance of 30 miles in a day was considered near miraculous, and it couldn't be maintained. A sustainable rapid advance was on the order of five to ten miles per day. But the Mongols could move fifty miles per day and keep it up for weeks. No army in history has ever moved overland as rapidly as the Mongols.