Saturn's satellite Iapetus (or Japetus) is one of the strangest objects in our Solar system. There is equatorial ridge about 20 km wide and 13 km high extending 1300 km through the center of Cassini Regio. Parts of the ridge rise more than 20 km over the surrounding plains. The ridge forms a complex system including isolated peaks, segments extending for more than 200 km and sections with three near parallel ridges. A an conclusion I'd say that all this seems to be way too unnatural in my opinion.