Geological Footprints in Ares Vallis
Numerous channels flow northward out of the Martian southern highlands and empty onto Chryse Planitia. These channels saw gigantic floods - as large or larger than any on Earth - early in Martian history. This was a time when Mars likely had a thicker atmosphere and a warmer climate. While Ares Vallis is not the widest or deepest outflow channel, it has a length of nearly 1,600 kilometers (1,000 miles).