The ecoregion is small, only 100 km from west to east, and 25 km from south to north. It covers the northern ridges and valleys of the Tarvagatai Range of the Khangai Mountains, at elevations of . Stream valleys drain the slopes northward into the Ider River, which runs below the northern edge of the ecoregion. The northernmost slopes of Mongolia's Tarvagatai Nuruu National Park are in the ecoregion.