It’s very convenient to travel by train or metro in South Korea.
If you have a chance, take a high speed train KTX (Korea Train Express). They are not so cheap, as slower trains, but nicer. 🙂
You can buy tickets at the counter in the train station, from a ticket machine or online.
Busan is the South Korea’s second largest city and its largest port city.
It’s famous among Koreans for beaches and festivals, e.g., Busan International Film Festival.
Busan is located about 450 km away from Seoul and the trip with fast train takes up to 2.5 h.
Nearby Seoul, there is located a very interesting Korean Folk Village.
I think it’s a great place to learn about Korean traditions and culture. Some places, may be too tourist or too kitschy these days, but I still recommend to check some performances. I liked all “crafting/ceramics” activities. I had also a chance to eat Korean traditional rice cakes. 🙂
I had the impression that many (or many older) Koreans are fit and love nature and hiking mountains or skiing.
When you’re in Seoul, visit beautiful Bukhansan National Park and try to climb the Bukhansan Mountain.
I can only add that in autumn, the mountains look wonderful with all colorful trees. 🙂
Gyeongbokgung Palace is on the top of my list with attractions of Seoul.
Gyeongbokgung Palace was built in 1395, however later was destroyed and then restored.
Besides the buildings of the palace, I enjoyed watching the ceremony of the changing of the guard, but probably I was more impressed by their clothes and weapons; very unique and colorful.
I was in Korea 9 years ago, in fall, and there were not so many tourists, what was very nice.
Changdeokgung Palace with its lovely Secret Garden is also a must-visit site in Seoul.
The other places I can highly recommend are:
-Bukhansan National Park
-Korean Demilitarized Zone (DMZ) located 60km from Seoul.
Koreans have very unique traditional clothes, especially female clothing is quite interesting. Unfortunately, these days, people don’t wear these clothes so often; even for special occasions like wedding, brides often choose western dresses. But if you’re lucky, you can still meet people wearing traditional clothing in South Korea. 🙂