More relevant from the wikipedia link: "Despite its name, it is often regarded as the world's largest lake, though it contains an oceanic basin (contiguous with

More relevant from the wikipedia link: "Despite its name, it is often regarded as the world's largest lake, though it contains an oceanic basin (contiguous with the world ocean until 11 million years ago) rather than being entirely over continental crust." Regardless, whether it's the largest or not isn't really the point, it's just that it sounds interesting. I believe Manitoulin island (which is a bigger island in a smaller lake) has a similar island-lake recursion pattern. If you start looking at islands (not necessarily the largest ones), there are also several lake-island recursions (Lake Taal on Luzon island being one). And then one could rank the size of the recursive islands (or lakes) at the various levels. It's a lot like trainspotting in the end.