Holden Crater sits within a string of craters that look like a chain of alpine lakes connected by a stream. The crater offers tantalizing clues to the history of water on Mars. Running water carved deep gullies in the crater. Water also carried sediments onto the floor of a prospective lakebed. These deposits are more than 3 billion years old, dating back to a wetter period of early martian history. Geological studies suggest that a massive, catastrophic flood may have breached part of the crater rim that was holding back water. The water eventually disappeared. Later, wind eroded the surface and exposed ancient sediments. Winds also formed ripples and dunes that are still visible on the surface today. Holden Crater offers the opportunity to examine some of the most ancient rocks on Mars. Another benefit of the site is that the mission would not have to drive far to get there. The rover would land on top of a "bajada," a high plateau of material eroded from nearby cliffs.