The two are easily confused, but there is a world of difference between them: Pyongyang is the capital of nuclear-armed North Korea, while Pyeongchang is the South Korean region hosting the Winter Olympics.
But away from the spotlight, these two unwanted guests, men dressed as North Korea supreme leader and the U.S. president, were escorted away from the premises.
Pyeongchang 2018 Olympics: The day in picturesParticipants perform during the opening ceremony of the Pyeongchang 2018 Winter Olympic Games.
On Friday, Pence said there was "no daylight" between the allies in pushing for denuclearization of the peninsula.
Believed to be in her late 20s, Kim Yo Jong shares the same mother as the North Korean leader and is seen as controlling access to him.
The two North Koreans are on a landmark visit to the South amid a flurry of abrupt reconciliation steps, and both attended the opening ceremony before having a luncheon with Moon at Moon's presidential palace earlier Saturday.
Apple's Smart Speaker HomePod Finally Hits The Market
One of the unanswered questions leading up to HomePod's launch has been how Apple's retail stores will display the speaker. With the launch, Apple is taking on existing smart speakers, such as the Amazon Echo ($100) and Google Home ($129).
Moon recalled his past visit to the North's Diamond Mountain resort, where he and his mother met his North Korean aunt during a temporary reunion of families separated by the 1950-53 Korean War.
Local media in South Korea initially reported that the technical disruptions were caused by some sort of cyberattack, but Olympic Games spokesman Sung Baik-you said there is no such evidence of such activity, at least not yet.
North Korean athletes "are not really participating in the Olympics", said the father of American student Otto Warmbier, who died a year ago after his release from imprisonment in North Korea. They were also served North Korean-style fermented fish and white "kimchi" or fermented cabbage.
"That mix", team leader Alan Ashley said, "really gives us a great opportunity".
The summit culminated in an eight-point agreement, built on the 2000 declaration.
But Warmbier insisted his attendance in South Korea was "not political". The North and the United States were also holding a series of high-level talks on Pyongyang's nuclear and missile programmes.
Short track is one of the most popular sports in South Korea and as a series of home skaters reached the later rounds of the men's 1,500 meters and the women's 500, the North Koreans celebrated by waving flags in support.
The early plan showed Pence, with his wife to the left and Moon to his right, seated across the round table from Kim, who was nestled between U.N. Secretary General António Guterres and International Olympics Committee President Thomas Bach's wife.