I am stationed in Korea for the first time (Yongsan). What advice do you have for navigating around the city?

You will love Yongsan, which was my first Korean tour in 1962, I was billeted at Camp Coiner and worked the Yongsan Eighth Army Communications Center. I had asked my houseboy to take me on a tour in Seoul. I bought guitars for both of us. (He probably sold his.)

Check out Iteawon outside of base and they have an Outback Steakhouse, South of the Border and other restaurants and bars. You can find YouTube videos about Itaewon

Get a T-Money card, load it with 20k won and learn the immediate surroundings. Know which gates go to which train entry ways and find landmarks that's hard to forget like a restaurant or public restroom. Took a few weeks for me but it's doable to travel to Casey or Humphreys by train. If you're not adventurous, at least learn what the main gates lead to and go to them via post bus. Best of luck out there!