Gullies in Noachis Terra (Natural Colors; credits: Lunar Explorer Italia)

Geologically young Gullies are a prime target for the HiRISE camera. Gullies are located in a variety of settings and are found all over Mars.
This "Ring Trough" or "Eroded Pit Crater", is located in the rugged Southern Highland Terrain known as Noachis Terra. The HiRISE image shows the layered, boulder-rich wall rock facing to the North-East and Gullies that are transporting material downslope.
The material collects into debris aprons along the walls, which often exhibit narrow channels along its surface.