Big sand ripple on the west side of the rover (three-frame composite from the Navcam).
NASA description (middle frame): This image was taken by Navcam: Left B (NAV_LEFT_B) onboard NASA’s Mars rover Curiosity on Sol 683 (2014-07-08 22:31:12 UTC).
Sol 683 raw images (from all cameras), and Curiosity’s latest location map.