When NASA's Opportunity rover paused to take in its surroundings earlier this month, it had quite a views. This is what it saw from the edge of the Endeavour Crater, a part of the planet that's been dubbed Marathon Valley.

The name's no coincidence: it happens to be where the little rover clocked up 26.21 miles of Mars trundling. But the valley does hold more allure than being a mile marker, because observations in this area are yielding samples of clay minerals that hint at ancient wet environments on the planet. Oh, and then there are the views. [NASA]

Image by NASA/JPL-Caltech/Cornell Univ./Arizona State Univ.