[3] Larger than Lake Superior on Earth, it is mostly composed of liquid methane, with unknown but lesser components of dissolved nitrogen and ethane, as well as other organic compounds.

The coast has numerous bays that appear to be flooded river mouths (rias), and unlike at Ontario Lacus there are no visible subaerial delta deposits, possible evidence of a recent sea level rise.

In the northeast and northwest sections of the mare, along about a quarter of the total shoreline, there are extensive areas where the depth is less than 5 m, shallow enough for imaging radar to penetrate to the bottom.

The "Magic Island" area only appeared in 2014 and may be waves, bubbles or subsurface ice rising to the surface as the lake warms up during spring, or possibly silt like material suspended in the liquid hydrocarbon sea.

[16] The Titan Lake In-situ Sampling Propelled Explorer (TALISE) was a conceptual design study for a Spanish lander mission envisioned to splash down and navigate across Ligeia Mare.

[17] In 2015, the NASA Innovative Advanced Concepts program (NIAC) awarded a Phase II grant[18] to a design study of a submarine to explore the seas of Titan.