Frankly I would rather take the Airport Limo Bus going forward (unless you are travelling very light) as it is too much hassle to take the AREX. We tried simply because of the downtown check-in privilege for Asiana Airlines passengers (Korean Air also included) and in case we experience any traffic jam taking the Airport Limo.
Left hotel 3.5hrs in advance. Took a cab to Seoul Station from Myeongdong. At Seoul station, had to lug our baggage up the ramp to take the lift down to basement level. There wasn't any clear signage indicating where to go so we really went with our instincts. The lifts took forever to come (only 2 serving this busy station) and there wasn't any dedicated lifts to the AREX.
Down at the basement level, it was quite confusing as we aren’t sure where to buy the AREX tickets and perform check-in. When we saw the check-in area we quickly head over but were stopped by the customer officers telling us that we have to purchase the AREX tickets first. After completing this, we head to the check-in counters only to be refused check-in as we were late by 20mins (due to our flight being brought forward by 10mins without any notification + the waiting for lifts + having to buy the AREX tickets first).
The downtown check-in sticks strictly to the 3hrs advance check-in (to ensure your checked in baggage gets on your flight on time) hence unless you leave for Seoul station 4 hours prior to your flight else you will face something we did. After we reach Incheon airport, we had to navigate a long way and go up the escalators before we finally reach Asiana check-in counters. Ended up we were late than early for check-in (left with 1hr 30mins before flight departure).
I had thought that taking the AREX will be smooth but turns out I was so wrong - it was a nightmare. Would prefer the airport limo bus as its really much more convenient compared to this so called faster direct to airport train which isn't any faster due to the hassle one has to go through.
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