Thailand is on the list of countries that have a "Visa Waiver Agreement" with the Republic of Korea, and Thai nationals are supposed to be able to enter ROK for up to 3 months without a visa. But I personally know one Thai lady that was denied entry with no explanation. She was stopped at the airport and held for 5 hours and then put on an airplane back to Thailand with no explanation. She a professional and is NOT in, or connected to, the "bargirl business". Needless to say, it was very embarrassing for her and she does not hold much good will towards Korea or Koreans right now.
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