Fallout: New Vegas locations project
Caterpillar's Mound is an island due south of the Sorrows encampment, it derives its name from the fact the rocks atop it resemble a caterpillar. By looking northwest from the dock at Sorrows Fork Campground, it can be seen directly ahead.
The rocks on the place where you get the xander roots is shaped like a caterpillar. Hence, the name Caterpillar's mound is given.
- PC The location may not show up as a marker on the compass mini map. [verified]