Here is some more good news for those who want to visit Korea but finding it tedious to apply for a short-term visitor visa. The Ministry of Justice or MOJ is allowing visitors in transit at the Incheon Airport to visit Seoul and other parts of the country without the need for a visa, even if the visitor in transit isn’t from an OECD country such as the United States, Japan and UK.
With the program, those who transfer at Incheon Airport to a third country or a domestic flight to Jeju Island, especially Chinese tour groups, will not need to be issued a visa. Foreign nationals transferring at Incheon Airport to a third country are able to enter Korea without a visa if they participate in one of the transit tourist programs permitted and operated by MCST or IIAC. Chinese tour groups heading to Jeju Island will be permitted to enter the country without a visa within twelve hours of arrival under the condition that they will go sightseeing in the Seoul metropolitan area. They will get an official entry permit once arriving on Jeju Island.
Read carefully the details of this new tourism policy of the Korean government. You might benefit from it ;p
No visa entry for transit passengers at Incheon Airport