Hellas Crater in the ancient highlands contains some of the clearest evidence on Mars for glacial processes. This image, on the eastern margin of the giant impact crater, shows a number of features consistent with glaciation.
There are roughly north-south running ridges and troughs which mark the deposition of sediment called moraine underneath or beside a glacier. There are also sinuous channels which may formed from meltwater underneath a glacier. A small (3.5 x 3.5 kilometer) cutout shows an example of the moraine and meltwater channel .
Written by: John Bridges (audio: Tre Gibbs) (13 August 2014)
More info and image formats at http://hirise.lpl.arizona.edu/ESP_036947_1390
Image: NASA/JPL/University of Arizona