I am Kazakhstani citizen flying from Australia to Kazakhstan with a long - 23 hours- stopover in Seoul Incheon Airport, and the same stopover on my way back. While stopping there I would like to walk in Seoul and get a hotel.
Do I need a visa for this?
According to Timatic:
Korea (Rep. of), South - Destination Visa
Visa required.
The following are exempt from holding a visa:
Nationals of Kazakhstan with a normal passport for a maximum stay of 30 days.
Thus you don't need a visa for this. Note that there's also a hotel in the airport itself, which might be more comfortable if you have an early flight.
Note that the trains to airport do not run at night; as far as I remember, there are no trains between midnight and 5:30am.
