From high on the rim, the creek runs generally north, entering Gila County almost immediately. It continues north through the wilderness to the confluence of an intermittent stream in Calf Pen Canyon, which enters from the right. Turning west, the creek receives another intermittent stream from the right in Sandrock Canyon, at the head of Fossil Creek Canyon. Before it reaches Fossil Springs, the creek becomes the boundary between Gila County on the stream's left and Yavapai County on its right, and it remains the boundary all the way to the Verde River.