HRSC: Craters within the Hellas basin

Scarring the southern highlands of Mars is one of the Solar System’s largest impact basins: Hellas, with a diameter of 2300 km and a depth of over 7 km. Hellas is thought to have formed between 3.8 and 4.1 billion years ago, when a large asteroid hit the surface of Mars…. Hellas has been subject to modification by the action of wind, ice, water and volcanic activity. Impact craters have also since pock-marked this vast basin floor… [More at link]