Vast level and usually treeless tracts in southeastern Europe or Asia or the arid land with vegetation found in regions of extreme temperature range and loess soil. This open grassland region is bounded on the north by forest, on the south by the Black Sea, the Caspian, and the mountains of central Asia. It supported nomadic pastoralists such as the Indo-Europeans, the Scythians, the Huns, and the Mongols. Their nomadic movements across the steppes spread cultural traits widely. The rich burials from Pazyryk are one of the few examples illustrating their wealth of material culture.