4k Resolution br br Images were taken by hazard-avoidance cameras on NASA's Mars Exploration Rover Opportunity between January 2004 and April 2015 as the rover traveled 26.2 miles (42.2 kilometers) from its landing location. A map of the rover's path is on the right. br br Audio is derived from vibration measurements from the rover's accelerometer; louder sound corresponds to rougher terrain and softer sound corresponds to smoother, sandy terrain.