Complex sentence: Dongguk university is loacated in Jung-gu, Seoul just below Namsan (Seoul), which the upper buildings of campus are directly connected into the trails of Namsan where many citizens enjoy stroll or picnic.
Split into simpler sentences: Dongguk university is located in Jung-gu, Seoul just below Namsan (Seoul). The upper buildings of the campus are directly connected into the trails of Namsan where many citizens enjoy a stroll or picnic.