I will be arriving Incheon Airport Terminal 2 at 5.45am and have another flight to Jeju that will depart at 8.55am from Gimpo Airport. Will it be ok if I were to take the AREX from Incheon Airport to Gimpo Airport? Considering the immigration, luggage collection etc.
My recollection I say you should be fine. I don’t think they offer any other service for airport transfers other than Cab. Super organized there so as long as the 1st flight is on time, you should be good.
Yes we did this same route earlier this year. You can catch the "ALL STOP" AREX train that goes from Incheon to Gimpo. Do NOT take the non stop Seoul only AREX train as that similar train will take you direct into Seoul. When you buy the train pass/ticket at ICN airport, ask the rep at the airport which one is "ALL STOP". The only delays which are questionable is the immigrations and customs depending on how many flights ahead of yours. Once on the train, it's about 20 minutes to GMP airport.
I should be clear, I used the subway and limo to make my connections between airports.
You will find that Korea is much further ahead of the USA in terms of getting you through the airport quickly, politely and efficiently. When they visit the U.S. they must think we are a 3rd world county. I took the subway on my way to Jeju and the limo back. Time is about the same, maybe an hour or less. The subway is easy and clean but you don't see much. Cost is comparable or at least not a factor. I think you will be fine and if you did miss the connection you probably would find that dealing with the airline there is much better then dealing with the airlines in the U.S.
I wish I had more facts. Since I only went from airport to Seoul Station on the express. I do know that in Seoul Station they offer an express checkin for Incheon but not sure if there is one for the other domestic airport. It is much closer to Seoul so perhaps a taxi from Seoul station if time is tight. It is about 45 nonstop from Incheon to Seoul Station.
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