For anyone visiting Korea I’d definitely recommend booking a tour of the DMZ. The DMZ or DeMilitarized Zone is a buffer zone between South and North Korea set up after the Korean war. Most tours encompass a visit to the Peace Park, the Third Tunnel, Dorasan Station and Dora Observatory. It’s “touristy” at times but overall well worth the money in a history lesson alone. It’s an early morning start and runs till late afternoon so it’s easily doable in between all the shopping, eating and drinking Seoul has to offer.