The Cheongju Municipal Chapter of Chungcheongbuk-do (Chungbuk) (Head: Lee Myeong-sik) held an event titled "Unification Golden Bell," which was modeled after a popular Korean TV quiz show for high school students, as part of its efforts to raise interest in unification and enhance historical awareness among Cheongju citizens.

Held at Cheongju Indoor Gymnasium at 2 pm on April 9, 2015, the “2015 History Golden Bell for Cheongju Citizens" was joined by more than 350 citizens including Mayor Lee Seung-hoon. Under the slogan "unification and harmony," the event was preceded by the performance of Pyongyang Arirang Arts Company. After the opening ceremony, 120 people advanced to the main round by passing the preliminary round of true or false quiz. Those who failed to answer the questions correctly were eliminated from the quiz contest until only the last person to answer the toughest question remained.

Lee In-woo, a 50-year-old man from Yongam-dong, Cheongju, won first place; Nakasima Harumi, who represented the community of multicultural families, received a special award. The oldest person who participated in the event was Park Yong-jeong, who was 83 years old.