At https://news.cornell.edu/stories/2018/01/saturns-moon-titan-sports-earth… …. using Cassini data Cornell astronomers have created a topographical image of Titan. It revealed several new features – such as mountains (no higher than 700m so perhaps better to describe them as hills). Two locations in the equatorial region are depressions. Titan also has three seas (on the surface) and they have a common sea level (just like the Earth). They are measuring Titan's geoid – the shape that the surface would take under the influence of gravity and rotation.