If you get a chance for a stopover in Seoul, I highly recommend it! The airport is hands down my favorite on the globe.
I flew Asiana Airlines to/from India & did not realized until a couple of days before takeoff that I would have an overnight layover in Seoul on both journeys. Luckily I found that a visa would not be required to enter South Korea so I jumped on Hostelworld & booked a bunk at Seoul I Guesthouse. It’s a decent spot, cheap, and in a fun neighborhood. If you have a daytime layover the airport offers a day tour service for free.
The metro connects directly to the airport which is easy. Nightlife is BIG in Korea. I couldn’t believe how many bottles of booze were around! People dress very nicely. Food is everywhere, everything, so good.
