There is the main singletrack trail that heads SSW up the mountain from the lodge generally following a drainage. There are also lots of other fun, loosely connected singletrack and two track in the forest and on the grassy slopes. These have been formed by cattle and jeeps. Great place to explore.
These trails are located on the far north end of a small mountain range on the west side of the highway. In this north end there is a good 25 miles of trails and two track. There is also some fun no track riding to be found on the grassy slopes and big ridges.
This north end/area of this range is bounded on its southern most extent by the road to Dugan Khad Camp. This dirt road begins 11km to the south on the road to Darkhan (closer to the turn to Bornuur). The entire mountain range is approximately 700-750 sq mi (~1900 sq km). Geologically, it is actually an extreme SW extension of the Hentii Mountain region.