I’m Korean-American and spent half my childhood there, and was there a couple years ago, so semi-recently. 🙂
Incheon is a completely separate city to Seoul! (Think: General MacArthur’s Incheon Landing during the hot phase of the Korean War.) It’s the primary international airport though, and it’s only about an hour to Seoul – you can very easily take the train. (The older Gimpo Airport is the one in Seoul and is international on a technicality although IIRC it only serves China and Japan. Also notably once listed as one of the world’s five WORST airports, lol.) There are buses to various locations from Incheon, which cost less but would be much trickier for a non-Korean-speaker to figure out.
Seconded on politeness words – you will also go far if you get in the habit of bowing to people (other adults). If you’re visibly foreign, people won’t expect you to have mastered all the nuances; in the cities people will give you points for making the effort. 🙂 ALSO. If you are invited indoors to visit someone, take your shoes off. Traditional-style restaurants will also have a place by the door to leave your shoes. And it will indeed be quite cold; same latitude as New York state, prepare accordingly. That said, the street food is IMO amazing, and that time of year will usually include everything from roasted chestnuts to various spicy dishes to hotteok (pancakes stuffed with semi-melted brown sugar, jujubes, and pine nuts). (Note that if you are vegetarian/vegan or have other special dietary requirements, you will have a hard time outside Seoul and/or major cities and you should specifically look into places that accommodate foreigners; don’t assume a random Korean restaurant, especially one serving traditional food, will know what to do about this. People will be baffled and/or not comprehend that no, a bit of shrimp paste makes it not vegetarian, etc. Your average Korean will never even have heard of things like kosher either. Signed, that one time a family member brought an American significant other who was vegan to visit.)
I have never seen anyone ask for ID on a subway but maybe that’s changed since I lived there? The subways are indeed safe. In Seoul proper, they have labels and announce stops in Korean, English, Japanese, and some flavor of Mandarin Chinese (not sure whether it’s traditional or simplified, I don’t speak/reaad Chinese). There’s high-speed rail that will cross the entire country in under 3 hours, which can also be fun!
You could have fun Googling “Korean national treasure” – S Korea has a system wherein not just artifacts and sites but *people* can be designated national treasures for cultural importance. Wikipedia has a list, if you want a crib sheet of cultural/historical things!
Gyeongbokgung (Palace) is a park now, with gorgeous architecture that might be interesting. Across the street they rent hanbok to tourists and you get free entry if you wear one to the park. Note that a lot of the traditional-style architecture got, well, bombed to heck and gone during the hot phase of the Korean War so what’s left most places is a lot of rectangular prism brutalism. Also for traditional architecture, I recommend Namdaemun, the old South Gate to the city. (Now smack in downtown, lol.) It’s smack next to Namdaemun Market, which can be fun.
If you like bookstores, the big one is Kyobo Bookstore (교보문고 / Kyobo Mungo) in Gwanghwamun. There are other locations, but that one has a notable statue of King Sejong, who invented the Korean alphabet. I find that Kyobo also tends to carry English-language books on Korean history that are a PITA to source outside of S Korea, ask me how I know.
If you’re curious about the alphabet, the Hunminjeongeum (훈민정음) was King Sejong’s document introducing it. An original copy is IIRC on display at Gansong Art Museum in Seoul. That said, any given museum for historical documents/art even in places like my mom’s home in the boonies will randomly have 1,000-year old silk calligraphy scrolls in its collection, it’s wild.
Seconded: National Museum of Korea. They will almost certainly have some dang Silla antler crown on display. I think the going theory is that this indicates a general anthropological/archaeological relationship to steppes peoples with shaman-ish crowns from when our precursors rode down into the peninsula and couldn’t find our way out. XD Likely also to have bunches of celadon (pottery) and so on.
Cheonmachong (Heavenly Horse Tomb) is in Gyeongju (to the south), if you like archaeological sites; it dates back to the Silla Dynasty (earlier than Joseon, which was the last one before the Japanese occupation). Gyeongju also has Cheomseongdae, the oldest East Asian astronomical observatory, which is IMO also the world’s shortest, squattest observatory, but everything down to the number of stones has some kind of astronomical significance (e.g. it’s made of 362 blocks for the days of the lunar year).
Korean Folk Village is in Yongin, if you want to see reenactments of folk rituals, historical costume, traditional-style landscaping, etc.
You might enjoy visiting a Buddhist temple or two in a tourist way. (The ones open for this kind of thing typically take donations.) I don’t have specific recs here since I can’t remember which one I was dragged to as a resentful small child, but the architecture is pretty.
Have fun! 😀
