The Boots-n-All travel guide network recently published their listing of the 7 top lesser known islands in the world and leading the list was South Korea’s own Cheju Island:

Jeju Island’s fame is as limited as that of the country to which it belongs, and for similarly strange reasons, considering that both have much to offer to even the most well-traveled.  Though by no means a tropical island, with sea temperatures warm enough to swim without a wetsuit only during July and August, its winters are mild and its landscape is beautiful throughout the year.  [Boots-n-All]

I do have to say that the list that Boots-n-All came up with features a couple of islands I wouldn’t consider as being lesser known such as the Whitsundays and the Azores. Jeju I would also say Cheju is not Korea’s best “lesser known” island.  I would rank Ulleungdo as being the best lesser known island in Korea.