I think that, of all the places I visited in Seoul, Mt. Namsan was among my favorites.
Mt. Namsan has a perfect location: it is almost in the middle of Seoul, smack dab between Itaewon and downtown.
From the top of Mt. Namsan, you can (on a clear day) see everything that there is to see. Unfortunately, ours was not a clear day, but still.
We took the train to Myeongdong and then took the cable car up Mt Namsan.
The views from the top were great and we admired the "love locks," a local tradition. I've seen these elsewhere, but apparently they are a particular favorite at Mt. Namsan.
The top of the mountain is a park all its own, with space for concerts, cultural exhibitions, and a cafe, as well as the observation tower and its famous restaurant.
We didn't go up N Seoul Tower as the visibility was not so good (which means I unfortunately can't tell you anything about whether the restrooms are as astonishing as they are alleged to be).
Instead we took the gorgeous hiking path back down the mountain and stopped at Namsangol Hanok village. Here the government has made a sort of park by moving several authentic Korean buildings here and restoring them and arranging the setting.
We took a break to eat lunch at a Chinese restaurant in Chungmuro. I must say it will be very hard to eat Asian food in California now that I have been to Seoul.